1
|
Cheng Y, Huh DN, Tonks IA. Mechanistic study of pyrazole synthesis via oxidation-induced N-N coupling of diazatitanacycles. Dalton Trans 2024; 53:9510-9515. [PMID: 38767913 DOI: 10.1039/d4dt01412j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Metal-mediated inner-sphere N-N coupling is an uncommon route to N-N bond formation. Herein, we report a mechanistic study of pyrazole formation via oxidation-induced N-N coupling of diazatitanacycles. In TEMPO oxidation reactions, the first of two oxidations is rate limiting and TEMPO coordination to Ti is critical for reactivity. In oxidations with Fc+ salts, coordinating counteranions such (eg. Cl-) aid an "inner-sphere-like" oxidation.
Collapse
Affiliation(s)
- Yukun Cheng
- Department of Chemistry and Chemical Biology, Cornell University, 365 Spencer T. Olin Research Wing, Ithaca, New York, USA
| | - Daniel N Huh
- Department of Chemistry, University of Rhode Island, Kingston, Rhode Island, USA
| | - Ian A Tonks
- Department of Chemistry, University of Minnesota, 207 Pleasant St SE, Minneapolis, Minnesota, USA.
| |
Collapse
|
2
|
Bruckhoff T, Paschai Darian LK, Stein CAM, Ballmann J. [PNP]-Stabilized Niobium(IV) and Tantalum(IV) Complexes: Synthesis and Characterization of an Open-Shell Tantalum Alkylidene. Organometallics 2023. [DOI: 10.1021/acs.organomet.3c00044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Affiliation(s)
- Tim Bruckhoff
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, D-69120 Heidelberg, Germany
| | - Leon K. Paschai Darian
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, D-69120 Heidelberg, Germany
| | - Carolin A. M. Stein
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, D-69120 Heidelberg, Germany
| | - Joachim Ballmann
- Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, D-69120 Heidelberg, Germany
| |
Collapse
|
3
|
Cobalt(II) complexes of α-diimine derived from cycloalkylamines as controlling agents for organometallic mediated radical polymerization of vinyl acetate. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114870] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
4
|
Minami Y, Furuya Y, Hiyama T. Facile Construction of Furanoacenes by a Three-Step Sequence Going through Disilyl-exo-cyclic Dienes. Chemistry 2020; 26:9471-9474. [PMID: 32181527 DOI: 10.1002/chem.202001119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Indexed: 11/07/2022]
Abstract
Facile synthesis of various benzonaphthofurans was achieved by intramolecular hydroarylation of 1,4-disilyl-2-aryloxy-1,3-enynes followed by cycloaddition with arynes or alkenes and finally desilylaromatization. The three-step transformation can be operated sequentially in one-pot, providing with a range of furanoacenes easily and highly effectively.
Collapse
Affiliation(s)
- Yasunori Minami
- Interdisciplinary Research Center for Catalytic Chemistry, National Institute of Advanced Industrial Science and Technology, 1-1-1, Higashi, Tsukuba, Ibaraki, 305-8565, Japan.,Research and Development Initiative, Chuo University, 1-13-27, Kasuga, Bunkyo-ku, Tokyo, 112-8551, Japan
| | - Yuki Furuya
- Department of Applied Chemistry, Chuo University, 1-13-27, Kasuga, Bunkyo-ku, Tokyo, 112-8551, Japan
| | - Tamejiro Hiyama
- Research and Development Initiative, Chuo University, 1-13-27, Kasuga, Bunkyo-ku, Tokyo, 112-8551, Japan
| |
Collapse
|
5
|
Zhang X, Zhou S, Fang X, Zhang L, Tao G, Wei Y, Zhu X, Cui P, Wang S. Syntheses of Dianionic α-Iminopyridine Rare-Earth Metal Complexes and Their Catalytic Acitivities toward Dehydrogenative Coupling of Amines with Hydrosilanes. Inorg Chem 2020; 59:9683-9692. [PMID: 32602707 DOI: 10.1021/acs.inorgchem.0c00907] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reactions of [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 with aminomethylene-substituted pyridine 2-[O(CH2CH2)2NCH2CH2NCH2]C5H4N (1) gave the dianionic α-iminopyridine rare-earth metal amido complexes {μ-η2:σ1:κ1:κ1-2-[O(CH2CH2)2NCH2CH2NCH]C5H4N}2RE2[N(SiMe3)2]2 (RE = Y(2a), La(2b), Pr(2c), Nd(2d), Sm(2e), Dy(2f), Er(2g), and Lu (2h)). However, reaction of [(Me3Si)2N]3Y(μ-Cl)Li(THF)3 with pyridin-2-ylmethyl-substituted amines such as 2-(RNHCH2)C5H4N (R = tBu (3a) and 2,6-iPr2Ph (3b)) or benzyl-substituted amine O(CH2CH2)2NCH2CH2NHCH2C6H5 (5) afforded the corresponding yttrium complexes containing monoanionic ligands [2-(RNCH2)C5H4N]2YN(SiMe3)2 (R = tBu (4a) and 2,6-iPr2Ph (4b)) or [O(CH2CH2)2NCH2CH2NCH2C6H5][(Me3Si)2N)]Y(μ-Cl)(μ-η3-O(CH2CH2)2NCH2CH2NCH2C6H5)Li(THF) (6). Dianionic α-iminopyridine rare-earth metal amido complexes showed high catalytic activities for the dehydrogenation coupling reaction of hydrosilanes and amines providing a variety of silylamines in high yields.
Collapse
Affiliation(s)
- Xiuli Zhang
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Shuangliu Zhou
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Xiaofei Fang
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Lijun Zhang
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Guide Tao
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Yun Wei
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Xiancui Zhu
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Peng Cui
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China
| | - Shaowu Wang
- Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241000, China.,Anhui Laboratory of Clean Catalytic Engineering, Anhui Laboratory of Functional Complexes for Materials Chemistry and Application, College of Biological and Chemical Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, PR China
| |
Collapse
|
6
|
Reactions of Dihaloboranes with Electron-Rich 1,4-Bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadienes. Molecules 2020; 25:molecules25122875. [PMID: 32580464 PMCID: PMC7356994 DOI: 10.3390/molecules25122875] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/14/2020] [Accepted: 06/16/2020] [Indexed: 11/16/2022] Open
Abstract
The reactions of electron-rich organosilicon compounds 1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (1), 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (2), and 1,1'-bis(trimethylsilyl)-1,1'-dihydro-4,4'-bipyridine (12) with B-amino and B-aryl dihaloboranes afforded a series of novel B=N-bond-containing compounds 3-11 and 13. The B=N rotational barriers of 7 (>71.56 kJ/mol), 10 (58.79 kJ/mol), and 13 (58.65 kJ/mol) were determined by variable-temperature 1H-NMR spectroscopy, thus reflecting different degrees of B=N double bond character in the corresponding compounds. In addition, ring external olefin isomers 11 were obtained by a reaction between 2 and DurBBr2. All obtained B=N-containing products were characterized by multinuclear NMR spectroscopy. Compounds 5, 9, 10a, 11, and 13a were also characterized by single-crystal X-ray diffraction analysis.
Collapse
|
7
|
Mashima K. Redox-Active α-Diimine Complexes of Early Transition Metals: From Bonding to Catalysis. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2020. [DOI: 10.1246/bcsj.20200056] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
8
|
Yoshida M, Yanagida S, Saito D, Kobayashi A, Kato M. Aromatic versus Aliphatic α-Diimine Ligands in Heteroleptic Copper(I) Emitters: Photophysical and Electrochemical Properties. ANAL SCI 2020; 36:67-73. [PMID: 31685717 DOI: 10.2116/analsci.19sap07] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The electrochemical and photophysical properties of a heteroleptic Cu(I) complex bearing an aliphatic α-diimine ligand, [Cu(dab)(xantphos)]+ (Cu-dab; dab = N,N'-diphenyl-2,3-dimethyl-1,4-diazabutadiene, xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene), were evaluated together with those of complexes [Cu(dmp)(xantphos)]+ (Cu-dmp; dmp = 2,9-dimethyl-1,10-phenanthroline), [Cu(dmbpy)(xantphos)]+ (Cu-dmbpy; dmbpy = 5,5'-dimethyl-2,2'-bipyridine), and [Cu(bq)(xantphos)]+ (Cu-bq; bq = 2,2'-biquinoline), bearing aromatic diimine ligands. Cu-dab exhibited a two-step ligand-centered redox behavior, where the first wave corresponded to an electrochemically reversible one-electron reduction process. Although Cu(I)-aromatic diimine complexes Cu-dmp, Cu-dmbpy, and Cu-bq exhibited obvious luminescence from the metal-to-ligand charge transfer (MLCT) excited state, Cu-dab did not show any luminescence. Computational studies indicated that this non-luminescent property was caused by the large structural relaxation of Cu-dab during photoexcitation.
Collapse
Affiliation(s)
- Masaki Yoshida
- Department of Chemistry, Faculty of Science, Hokkaido University
| | - Sae Yanagida
- Department of Chemistry, Faculty of Science, Hokkaido University
| | - Daisuke Saito
- Department of Chemistry, Faculty of Science, Hokkaido University
| | | | - Masako Kato
- Department of Chemistry, Faculty of Science, Hokkaido University
| |
Collapse
|
9
|
Kawakita K, Kakiuchi Y, Beaumier EP, Tonks IA, Tsurugi H, Mashima K. Synthesis of Pyridylimido Complexes of Tantalum and Niobium by Reductive Cleavage of the N═N Bond of 2,2'-Azopyridine: Precursors for Early-Late Heterobimetallic Complexes. Inorg Chem 2019; 58:15155-15165. [PMID: 31553585 PMCID: PMC7017918 DOI: 10.1021/acs.inorgchem.9b02043] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the syntheses of 2-pyridylimido complexes of tantalum and niobium by N═N bond cleavage of 2,2'-azopyridine. Reaction of MCl5 (M = Ta and Nb) with 2,2'-azopyridine in the presence of 0.5 equiv of 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene (abbreviated Si-Me-CHD) afforded a dark red solution (for Ta) and a dark blue solution (for Nb) with some insoluble precipitates. After removing the solids, another 0.5 equiv of Si-Me-CHD was added to each solution, giving [M(═Npy)Cl3]n (1a: M = Ta; 1b: M = Nb) through reductive cleavage of the N═N bond of 2,2'-azopyridine. The initial products of the above reactions were determined to be 2,2'-azopyridine-bridged dinuclear complexes, [(MCl4)2(μ-pyNNpy)] (2a: M = Ta; 2b: M = Nb), which were isolated by treating MCl5 with 2,2'-azopyridine and Si-Me-CHD in a 2:1:1 molar ratio. In 2a and 2b, the N═N bond was reduced to a single bond via two-electron reduction. Further reduction of complexes 2a and 2b with 1 equiv of Si-Me-CHD afforded complexes 1a and 1b. An anionic doubly μ-imido-bridged ditantalum complex, [nBu4N][Ta2(μ-Npy)2Cl7] (3a), was generated upon addition of nBu4NCl to complex 1a, while addition of nBu4NCl to niobium complex 1b gave a polymeric terminal imido complex, [nBu4N]n/2[{Nb(═Npy)Cl3}2(μ-Cl)]n/2 (3b). Complexations of 1a and 1b with 1 equiv of 2,2'-bipyridine resulted in the formation of mononuclear 2-pyridylimido complexes, M(═Npy)Cl3(bipy) (4a: M = Ta; 4b: M = Nb), whose main structural feature is intramolecular hydrogen bonding between the ortho hydrogen atom of 2,2'-bipyridine and the nitrogen atom of the pyridyl group on the imido ligand. Isolated 2-pyridylimido complexes 4a and 4b reacted with [RhCl(cod)]2 to produce the corresponding early-late heterobimetallic complexes, (bipy)MCl3(μ-Npy)RhCl(cod) (5a: M = Ta; 5b: M = Nb).
Collapse
Affiliation(s)
- Kento Kawakita
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Yuya Kakiuchi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Evan P. Beaumier
- Department of Chemistry, University of Minnesota–Twin Cities, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Ian A. Tonks
- Department of Chemistry, University of Minnesota–Twin Cities, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
10
|
Parker BF, Hosoya H, Arnold J, Tsurugi H, Mashima K. α-Diimine-Niobium Complex-Catalyzed Deoxychlorination of Benzyl Ethers with Silicon Tetrachloride. Inorg Chem 2019; 58:12825-12831. [PMID: 31498599 DOI: 10.1021/acs.inorgchem.9b01784] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
α-Diimine niobium complexes serve as catalysts for deoxygenation of benzyl ethers by silicon tetrachloride (SiCl4) to cleanly give two equivalents of the corresponding benzyl chlorides, where SiCl4 has the dual function of oxygen scavenger and chloride source with the formation of a silyl ether or silica as the only byproduct. The reaction mechanism has two successive trans-etherification steps that are mediated by the niobium catalyst, first forming one equivalent of benzyl chloride along with the corresponding silyl ether intermediate that undergoes the same reaction pathway to give the second equivalent of benzyl chloride and silyl ether.
Collapse
Affiliation(s)
- Bernard F Parker
- Department of Chemistry, Graduate School of Engineering Science , Osaka University , Toyonaka , Osaka 560-8531 , Japan.,Department of Chemistry , University of California , Berkeley , California 94720 , United States
| | - Hiromu Hosoya
- Department of Chemistry, Graduate School of Engineering Science , Osaka University , Toyonaka , Osaka 560-8531 , Japan
| | - John Arnold
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
| | - Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science , Osaka University , Toyonaka , Osaka 560-8531 , Japan
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science , Osaka University , Toyonaka , Osaka 560-8531 , Japan
| |
Collapse
|
11
|
Nishiyama H, Hosoya H, Parker BF, Arnold J, Tsurugi H, Mashima K. Hydrodehalogenation of alkyl halides catalyzed by a trichloroniobium complex with a redox active α-diimine ligand. Chem Commun (Camb) 2019; 55:7247-7250. [PMID: 31165806 DOI: 10.1039/c9cc03268a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A high-valent d0 niobium(v) complex, (α-diimine)NbCl3 (1), bearing a dianionic redox-active α-diimine ligand served as a catalyst for a hydrodehalogenation reaction of alkyl halides in the presence of PhSiH3. During the catalytic reaction, the redox-active α-diimine ligand allowed the complex to reversibly release and accept one-electron through switching its coordination mode between a dianionic folded form and a monoanionic planar one.
Collapse
Affiliation(s)
- Haruka Nishiyama
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
| | - Hiromu Hosoya
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
| | - Bernard F Parker
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan. and Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | - John Arnold
- Department of Chemistry, University of California, Berkeley, California 94720, USA.
| | - Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
| |
Collapse
|
12
|
Lu Z, Lavendomme R, Burghaus O, Nitschke JR. A Zn
4
L
6
Capsule with Enhanced Catalytic C−C Bond Formation Activity upon C
60
Binding. Angew Chem Int Ed Engl 2019; 58:9073-9077. [DOI: 10.1002/anie.201903286] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 04/20/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Zhenpin Lu
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Roy Lavendomme
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Olaf Burghaus
- Fachbereich ChemiePhilipps-Universität Marburg Hans-Meerwein-Str. 4 35032 Marburg Germany
| | - Jonathan R. Nitschke
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| |
Collapse
|
13
|
Lu Z, Lavendomme R, Burghaus O, Nitschke JR. A Zn
4
L
6
Capsule with Enhanced Catalytic C−C Bond Formation Activity upon C
60
Binding. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201903286] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Zhenpin Lu
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Roy Lavendomme
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| | - Olaf Burghaus
- Fachbereich ChemiePhilipps-Universität Marburg Hans-Meerwein-Str. 4 35032 Marburg Germany
| | - Jonathan R. Nitschke
- Department of ChemistryUniversity of Cambridge Lensfield Road Cambridge CB2 1EW UK
| |
Collapse
|
14
|
Skatova AA, Bazyakina NL, Fedushkin IL, Piskunov AV, Druzhkov NO, Cherkasov AV. Mononuclear gallium complexes with the redox-active dmp-bian ligand (dmp-bian is 1,2-bis[(2,6-dimethylphenyl)imino]acenaphthene): synthesis and reactions with alkynes. Russ Chem Bull 2019. [DOI: 10.1007/s11172-019-2383-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
15
|
Tsurugi H, Mashima K. Salt-Free Reduction of Transition Metal Complexes by Bis(trimethylsilyl)cyclohexadiene, -dihydropyrazine, and -4,4'-bipyridinylidene Derivatives. Acc Chem Res 2019; 52:769-779. [PMID: 30794373 DOI: 10.1021/acs.accounts.8b00638] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Chemical reduction of transition metals provides the corresponding low-valent transition metal species as a key step for generating catalytically active species in metal-assisted organic transformations and is a fundamental unit reaction for preparing organometallic complexes. A variety of metal-based reductants, such as metal powders and organometallic reagents of alkali and alkaline-earth metals, have been developed to date to access low-valent metal species. During the reduction, however, reductant-derived metal salts are formed as reaction waste, some of which often interact with the reactive low-valent metal center, thereby disrupting the catalytic performance and hampering the isolation of organometallic complexes as a result of salt coordination to the coordinatively unsaturated vacant and active sites and the formation of thermally unstable ate complexes. In this Account, we emphasize the synthetic utility and versatility of organic reductants containing two trimethylsilyl groups, i.e., 1,4-bis(trimethylsilyl)cyclohexa-2,5-diene (1a) and its methyl derivative (1b), 1,4-bis(trimethylsilyl)dihydropyrazine (2a) and its dimethyl (2b) and tetramethyl (2c) derivatives, and 1,1'-bis(trimethylsilyl)-4,4'-bipyridinylidene (3), leading to the reduction of various kinds of metal compounds in a salt-free fashion by release of two electrons together with the coproduction of easily removable (hetero)aromatics and trimethylsilyl derivatives from these organic reductants 1-3. When homoleptic chlorides of group 5 and 6 metals are treated with 1a and 1b, in situ-generated highly reactive low-valent metal species react with redox-active molecules such as ethylene, α-diimines, and α-diketones to produce metallacyclopentane, (ene-diamido)metal, and (ene-diolato)metal complexes, respectively. The advantage of the salt-free protocol is further exemplified in the low-valent titanocene-catalyzed Reformatsky-type reaction when 2c is used as a reductant: the yield of the product using the organosilicon reductant is higher than that when manganese powder is used as the reductant for the catalytic Reformatsky-type reaction of ethyl 2-bromoisobutyrate and its derivatives with various aldehydes. Moreover, when halides, carboxylates, and acetylacetonate compounds of late transition metals and main-group elements are treated with the organosilicon reductant 2c, metal(0) particles are smoothly precipitated under mild conditions. Among them, metallic nickel(0) nanoparticles are applicable to reductive biaryl formation and reductive cross-coupling of aryl halides/aryl aldehydes. In addition, reduction of the heterogeneous catalysts on a solid supporting matrix was also achieved by this salt-free reduction method; volatile byproducts are easily removed from the catalyst surface without suppressing the catalytic performance. Thus, the salt-free reduction strategy is a very powerful synthetic method that can be extended to various metals throughout the periodic table.
Collapse
Affiliation(s)
- Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
16
|
Heins SP, Zhang B, MacMillan SN, Cundari TR, Wolczanski PT. Oxidative Additions to Ti(IV) in [(dadi)4–]TiIV(THF) Involve Carbon–Carbon Bond Formation and Redox-Noninnocent Behavior. Organometallics 2019. [DOI: 10.1021/acs.organomet.8b00930] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Spencer P. Heins
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Bufan Zhang
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Samantha N. MacMillan
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Thomas R. Cundari
- Department of Chemistry, CASCaM, University of North Texas, Denton, Texas 76201, United States
| | - Peter T. Wolczanski
- Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| |
Collapse
|
17
|
Lohrey TD, Maron L, Bergman RG, Arnold J. Heterotetrametallic Re-Zn-Zn-Re Complex Generated by an Anionic Rhenium(I) β-Diketiminate. J Am Chem Soc 2019; 141:800-804. [PMID: 30571106 DOI: 10.1021/jacs.8b12494] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the synthesis of an anionic rhenium(I) compound, Na[Re(η5-Cp)(BDI)] (1; Cp = cyclopentadienide, BDI = N, N'-bis(2,6-diisopropylphenyl)-3,5-dimethyl-β-diketiminate) and initial investigations of its use as a strong chemical reductant and metalloligand. Chemical oxidation of 1 gives a rare example of a rhenium(II) compound Re(η5-Cp)(BDI) (2), while protonation of 1 yields the rhenium(III) hydride complex Re(H)(η5-Cp)(BDI) (3). The reaction of 1 with ZnCl2 generated both 2 and the zinc(I) compound [ZnRe(η5-Cp)(BDI)]2 (4), which features a linear, tetrametallic Re(I)-Zn(I)-Zn(I)-Re(I) core. Computational studies of 4 were performed to characterize the metal-metal bonding interactions; the results indicate a dative interaction from rhenium to zinc and covalent bonding between the two zinc centers. One-electron oxidation of 4 yielded both 2 and the triflate-bridged zinc(II) complex [(μ-OTf)ZnRe(η5-Cp)(BDI)]2 (5, OTf = trifluoromethanesulfonate).
Collapse
Affiliation(s)
- Trevor D Lohrey
- Department of Chemistry , University of California, Berkeley , Berkeley , California 94720 , United States.,Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Laurent Maron
- LPCNO , Université de Toulouse , INAS Toulouse, 135 Avenue de Rangueil , Toulouse 31077 , France
| | - Robert G Bergman
- Department of Chemistry , University of California, Berkeley , Berkeley , California 94720 , United States
| | - John Arnold
- Department of Chemistry , University of California, Berkeley , Berkeley , California 94720 , United States.,Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| |
Collapse
|
18
|
Beaumier EP, Pearce AJ, See XY, Tonks IA. Modern applications of low-valent early transition metals in synthesis and catalysis. Nat Rev Chem 2019; 3:15-34. [PMID: 30989127 PMCID: PMC6462221 DOI: 10.1038/s41570-018-0059-x] [Citation(s) in RCA: 132] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Low-valent early transition metals are often intrinsically highly reactive as a result of their strong propensity toward oxidation to more stable high-valent states. Harnessing these highly reducing complexes for productive reactivity is potentially powerful for C-C bond construction, organic reductions, small-molecule activation and many other reactions that offer orthogonal chemoselectivity and/or regioselectivity patterns to processes promoted by late transition metals. Recent years have seen many exciting new applications of low-valent metals through building new catalytic and/or multicomponent reaction manifolds out of classical reactivity patterns. In this Review, we survey new methods that employ early transition metals and invoke low-valent precursors or intermediates in order to identify common themes and strategies in synthesis and catalysis.
Collapse
Affiliation(s)
- Evan P. Beaumier
- Department of Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Adam J. Pearce
- Department of Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Xin Yi See
- Department of Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Ian A. Tonks
- Department of Chemistry, University of Minnesota, Minneapolis, MN, USA
| |
Collapse
|
19
|
Patra SC, Saha Roy A, Banerjee S, Banerjee A, Das Saha K, Bhadra R, Pramanik K, Ghosh P. Palladium(ii) and platinum(ii) complexes of glyoxalbis(N-aryl)osazone: molecular and electronic structures, anti-microbial activities and DNA-binding study. NEW J CHEM 2019. [DOI: 10.1039/c9nj00223e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A new family of palladium(ii) and platinum(ii) complexes of redox non-innocent osazone ligands that exhibit moderate antileishmanial activity were isolated.
Collapse
Affiliation(s)
- Sarat Chandra Patra
- Department of Chemistry
- R. K. Mission Residential College
- Kolkata-700103
- India
- Department of Chemistry
| | - Amit Saha Roy
- Department of Chemistry
- R. K. Mission Residential College
- Kolkata-700103
- India
- Department of Chemistry
| | - Saswati Banerjee
- Cancer Biology & Inflammatory Disorder
- Indian Institute of Chemical Biology
- Kolkata 700032
- India
| | - Ananya Banerjee
- Department of Chemistry
- Bijaygarh Jyotish Roy College
- Kolkata-700032
- India
| | - Krishna Das Saha
- Cancer Biology & Inflammatory Disorder
- Indian Institute of Chemical Biology
- Kolkata 700032
- India
| | - Ranjan Bhadra
- Department of Chemistry
- R. K. Mission Residential College
- Kolkata-700103
- India
| | | | - Prasanta Ghosh
- Department of Chemistry
- R. K. Mission Residential College
- Kolkata-700103
- India
| |
Collapse
|
20
|
Tsurugi H, Mashima K. A New Protocol to Generate Catalytically Active Species of Group 4-6 Metals by Organosilicon-Based Salt-Free Reductants. Chemistry 2018; 25:913-919. [PMID: 30047181 DOI: 10.1002/chem.201803181] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 07/19/2018] [Indexed: 11/10/2022]
Abstract
Herein, we provide a new protocol to reduce various transition-metal complexes by using organosilicon compounds in a salt-free fashion with the great advantage of generating pure low-valent metal species and metallic(0) nanoparticles, in sharp contrast to reductant-derived salt contaminants obtained by reduction with metal reductants. The organosilicon derivatives 1,4-bis(trimethylsilyl)-2,5-cyclohexadiene (1 a), 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene (1 b), 1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (2 a), 2,5-dimethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (2 b), 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (2 c), and 1,1'-bis(trimethylsilyl)-1H,1'H-4,4'-bipyridinylidene (3) all served as versatile reductants for early transition-metal complexes and produced only easy-to-remove organic compounds, such as trimethylsilylated compounds and the corresponding aromatics, for example, benzene, toluene, pyrazine, and 4,4'-bipyridyl, as the byproducts. The high solubility of the reductants in organic solvents enabled us to monitor the catalytic reactions directly and to detect any catalytically active species so that we could elucidate the reaction mechanism.
Collapse
Affiliation(s)
- Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3, Machikaneyama-cho, Toyonaka, Osaka, 5608531, Japan
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3, Machikaneyama-cho, Toyonaka, Osaka, 5608531, Japan
| |
Collapse
|
21
|
Zhang W, Dodonov VA, Chen W, Zhao Y, Skatova AA, Fedushkin IL, Roesky PW, Wu B, Yang XJ. Cycloaddition versus Cleavage of the C=S Bond of Isothiocyanates Promoted by Digallane Compounds with Noninnocent α-Diimine Ligands. Chemistry 2018; 24:14994-15002. [PMID: 30016556 DOI: 10.1002/chem.201802469] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/02/2018] [Indexed: 11/11/2022]
Abstract
Whereas the chemistry of single-bond activation by compounds of the main group elements has undergone some development in recent years, the cleavage of multiple bonds remains underexplored. Herein, the reactions of two digallanes bearing α-diimine ligands, namely, [L1 Ga-GaL1 ] (1, L1 =dpp-dad=[(2,6-iPr2 C6 H3 )NC(CH3 )]2 ) and [L2 Ga-GaL2 ] (2, L2 =dpp-bian=1,2-[(2,6-iPr2 C6 H3 )NC]2 C10 H6 ), with isothiocyanates are reported. Reactions of 1 or 2 with isothiocyanates in 1:2 molar ratio proceeded with [2+4] cycloaddition of the C=S bond across the C2 N2 Ga metallacycle with formation of C-C and S-Ga single bonds to afford [L1 (RN=C-S)Ga-Ga(S-C=NR)L1 ] (3, R=Me; 4, R=Ph) and [L2 (RN=C-S)Ga-Ga(S-C=NR)L2 ] (8, R=allyl; 9, R=Ph). In the cases of 8 and 9, this cycloaddition is reversible. The digallanes reacted with 2 equiv of PhNCS in the presence of Na metal or at high temperatures through a unique reductive cleavage of the C=S bond to yield the disulfide-bridged digallium species [Na(THF)3 ]2 [L1 Ga(μ-S)2 GaL1 ] (5), [L2 Ga(μ-S)2 GaL2 ] (10), and [Na(DME)3 ][L2 Ga(μ-S)2 GaL2 ] (11). Moreover, products 4 and 5 can further react with an excess of isothiocyanate, through cleavage of the C=S bond or cycloaddition, to give the bis- or mono-S-bridged complexes [Na(THF)2 ]2 [L1 (PhN=C-S)Ga(μ-S)2 Ga(S-C=NPh)L1 ] (6) and [L1 (PhN=C-S)Ga(μ-S)Ga(S-C=NPh)L1 ] (7). All the newly prepared compounds were characterized by elemental analysis, single-crystal X-ray diffraction, IR spectroscopy, NMR (3-9) or ESR spectroscopy (11), and DFT calculations.
Collapse
Affiliation(s)
- Wei Zhang
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of, the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China
| | - Vladimir A Dodonov
- G. A. Razuvaev Institute of Organometallic Chemistry of, Russian Academy of Sciences, Tropinina str. 49, Nizhny Novgorod, 603137, Russia.,Institute of Inorganic Chemistry, Karlsruhe Institute of Technology, Engesserstrasse 15, 76131, Karlsruhe, Germany
| | - Weixing Chen
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of, the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China
| | - Yanxia Zhao
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of, the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China
| | - Alexandra A Skatova
- G. A. Razuvaev Institute of Organometallic Chemistry of, Russian Academy of Sciences, Tropinina str. 49, Nizhny Novgorod, 603137, Russia
| | - Igor L Fedushkin
- G. A. Razuvaev Institute of Organometallic Chemistry of, Russian Academy of Sciences, Tropinina str. 49, Nizhny Novgorod, 603137, Russia
| | - Peter W Roesky
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology, Engesserstrasse 15, 76131, Karlsruhe, Germany
| | - Biao Wu
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of, the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China
| | - Xiao-Juan Yang
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of, the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710069, P. R. China
| |
Collapse
|
22
|
Haeri HH, Duraisamy R, Harmgarth N, Liebing P, Lorenz V, Hinderberger D, Edelmann FT. Electronic and Geometric Structures of Paramagnetic Diazadiene Complexes of Lithium and Sodium. ChemistryOpen 2018; 7:701-708. [PMID: 30202705 PMCID: PMC6123648 DOI: 10.1002/open.201800114] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Indexed: 11/08/2022] Open
Abstract
The electronic and molecular structures of the lithium and sodium complexes of 1,4-bis(2,6-diisopropylphenyl)-2,3-dimethyl-1,4-diazabutadiene (Me2DADDipp) were fully characterized by using a multi-frequency electron paramagnetic resonance (EPR) spectroscopy approach and crystallography, together with density functional theory (DFT) calculations. EPR measurements, using T1 relaxation-time-filtered pulse EPR spectroscopy, revealed the diagonal elements of the A and g tensors for the metal and ligand sites. It was found that the central metals in the lithium complexes had sizable contributions to the SOMO, whereas this contribution was less strongly observed for the sodium complex. Such strong contributions were attributed to structural specifications (e.g. geometrical data and atomic size) rather than electronic effects.
Collapse
Affiliation(s)
- Haleh H. Haeri
- Institute of ChemistryMartin Luther University Halle-WittenbergVon-Danckelmann-Platz 406120HalleGermany
| | - Ramesh Duraisamy
- Institute of ChemistryOtto-von-Guericke UniversityMagdeburg39106Germany
| | - Nicole Harmgarth
- Institute of ChemistryOtto-von-Guericke UniversityMagdeburg39106Germany
| | - Phil Liebing
- Laboratory for Inorganic ChemistryETH ZürichVladimir-Prelog-Weg 28093ZürichSwitzerland
| | - Volker Lorenz
- Institute of ChemistryOtto-von-Guericke UniversityMagdeburg39106Germany
| | - Dariush Hinderberger
- Institute of ChemistryMartin Luther University Halle-WittenbergVon-Danckelmann-Platz 406120HalleGermany
| | | |
Collapse
|
23
|
Sinha V, Pribanic B, de Bruin B, Trincado M, Grützmacher H. Ligand- and Metal-Based Reactivity of a Neutral Ruthenium Diolefin Diazadiene Complex: The Innocent, the Guilty and the Suspicious. Chemistry 2018; 24:5513-5521. [PMID: 29341297 PMCID: PMC5947567 DOI: 10.1002/chem.201705957] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Indexed: 11/17/2022]
Abstract
Coordination of the diazadiene diolefin ligand (trop2 dad) to ruthenium leads to various complexes of composition [Ru(trop2 dad)(L)]. DFT studies indicate that the closed-shell singlet (CSS), open-shell singlet (OSS), and triplet electronic structures of this species are close in energy, with the OSS spin configuration being the lowest in energy for all tested functionals. Singlet-state CASSCF calculations revealed a significant multireference character for these complexes. The closed-shell singlet wavefunction dominates, but these complexes have a significant (≈8-16 %) open-shell singlet [d7 -RuI (L)(trop2 dad.- )] contribution mixed into the ground state. In agreement with their ambivalent electronic structure, these complexes reveal both metal- and ligand-centered reactivity. Most notable are the reactions with AdN3 , diazomethane, and a phosphaalkyne leading to scission of the C-C bond of the diazadiene (dad) moiety of the trop2 dad ligand, resulting in net (formal) nitrene, carbene, or P≡C insertion in the dad C-C bond, respectively. Supporting DFT studies revealed that several of the ligand-based reactions proceed via low-barrier radical-type pathways, involving the dad.- ligand radical character of the OSS or triplet species.
Collapse
Affiliation(s)
- Vivek Sinha
- Supramolecular and Homogeneous Catalysis GroupVan 't Hoff Institute for Molecular Sciences (HIMS)University of AmsterdamScience park 9041098XHAmsterdamThe Netherlands
| | - Bruno Pribanic
- Department of Chemistry and Applied Biosciences ETH ZürichLaboratory of Inorganic ChemistryVladimir-Prelog-Weg 1ZürichCH-8093Switzerland
| | - Bas de Bruin
- Supramolecular and Homogeneous Catalysis GroupVan 't Hoff Institute for Molecular Sciences (HIMS)University of AmsterdamScience park 9041098XHAmsterdamThe Netherlands
| | - Monica Trincado
- Department of Chemistry and Applied Biosciences ETH ZürichLaboratory of Inorganic ChemistryVladimir-Prelog-Weg 1ZürichCH-8093Switzerland
| | - Hansjörg Grützmacher
- Department of Chemistry and Applied Biosciences ETH ZürichLaboratory of Inorganic ChemistryVladimir-Prelog-Weg 1ZürichCH-8093Switzerland
| |
Collapse
|
24
|
Bartalucci N, Bortoluzzi M, Zacchini S, Pampaloni G, Marchetti F. Activation of CN bonds by high-valent group 6 metal chlorides, including the conversion of an α-diimine into a functionalized imidazolium. NEW J CHEM 2018. [DOI: 10.1039/c8nj00846a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The direct interactions of WCl6and MoCl5with α-diimines (and also a carbodiimide in the case of MoCl5) have been explored, leading to unusual reaction pathways.
Collapse
Affiliation(s)
- Niccolò Bartalucci
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
| | - Marco Bortoluzzi
- CIRCC
- I-70126 Bari
- Italy
- Università Ca’ Foscari Venezia
- Dipartimento di Scienze Molecolari e Nanosistemi
| | - Stefano Zacchini
- CIRCC
- I-70126 Bari
- Italy
- Università di Bologna
- Dipartimento di Chimica Industriale “Toso Montanari”
| | - Guido Pampaloni
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
| | - Fabio Marchetti
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
| |
Collapse
|
25
|
Bartalucci N, Bortoluzzi M, Pampaloni G, Pinzino C, Zacchini S, Marchetti F. Stable coordination complexes of α-diimines with Nb(v) and Ta(v) halides. Dalton Trans 2018; 47:3346-3355. [DOI: 10.1039/c8dt00122g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Uncommon coordination compounds of high valent transition metal halides with N-aryl α-diimines have been obtained, without the need for reducing agents to quench the activation power of the metal centre.
Collapse
Affiliation(s)
- Niccolò Bartalucci
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
| | - Marco Bortoluzzi
- CIRCC
- I-70126 Bari
- Italy
- Università Ca’ Foscari Venezia
- Dipartimento di Scienze Molecolari e Nanosistemi
| | - Guido Pampaloni
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
| | | | - Stefano Zacchini
- CIRCC
- I-70126 Bari
- Italy
- Università di Bologna
- Dipartimento di Chimica Industriale “Toso Montanari”
| | - Fabio Marchetti
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
| |
Collapse
|
26
|
Bartalucci N, Bortoluzzi M, Funaioli T, Marchetti F, Pampaloni G, Zacchini S. Allowing the direct interaction of N-aryl α-diimines with a high valent metal chloride: one-pot WCl 6-promoted formation of quinoxalinium salts. Dalton Trans 2017; 46:12780-12784. [PMID: 28932841 DOI: 10.1039/c7dt03226a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The full potential of a high valent metal chloride as both a chlorinating and an oxidative agent was explored by allowing WCl6 to react with N-(2,6-diisopropylphenyl) α-diimines, in CH2Cl2 at room temperature. These α-diimines underwent unprecedented conversion to quinoxalinium cations via intramolecular C-N coupling.
Collapse
Affiliation(s)
- Niccolò Bartalucci
- University of Pisa, Dipartimento di Chimica e Chimica Industriale, Via Moruzzi 13, I-56124 Pisa, Italy. fabio.marchetti1974@ unipi.it
| | | | | | | | | | | |
Collapse
|
27
|
Meißner G, Feist M, Braun T, Kemnitz E. Selective reduction of a C Cl bond in halomethanes with Et3GeH at nanoscopic Lewis acidic Aluminium fluoride. J Organomet Chem 2017. [DOI: 10.1016/j.jorganchem.2017.04.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
28
|
Kriegel BM, Kaltsoyannis N, Chatterjee R, Bergman RG, Arnold J. Synthesis and Redox Chemistry of a Tantalum Alkylidene Complex Bearing a Metallaimidazole Ring. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00448] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Benjamin M. Kriegel
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Nikolas Kaltsoyannis
- School
of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Ruchira Chatterjee
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Robert G. Bergman
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - John Arnold
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| |
Collapse
|
29
|
Nishiyama H, Ikeda H, Saito T, Kriegel B, Tsurugi H, Arnold J, Mashima K. Structural and Electronic Noninnocence of α-Diimine Ligands on Niobium for Reductive C-Cl Bond Activation and Catalytic Radical Addition Reactions. J Am Chem Soc 2017; 139:6494-6505. [PMID: 28409626 DOI: 10.1021/jacs.7b02710] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A d0 niobium(V) complex, NbCl3(α-diimine) (1a), supported by a dianionic redox-active N,N'-bis(2,6-diisopropylphenyl)-1,4-diaza-2,3-dimethyl-1,3-butadiene (α-diimine) ligand (ene-diamido ligand) served as a catalyst for radical addition reactions of CCl4 to α-olefins and cyclic alkenes, selectively affording 1:1 radical addition products in a regioselective manner. During the catalytic reaction, the α-diimine ligand smoothly released and stored an electron to control the oxidation state of the niobium center by changing between an η4-(σ2,π) coordination mode with a folded MN2C2 metallacycle and a κ2-(N,N') coordination mode with a planar MN2C2 metallacycle. Kinetic studies of the catalytic reaction elucidated the reaction order in the catalytic cycle: the radical addition reaction rate obeyed first-order kinetics that were dependent on the concentrations of the catalyst, styrene, and CCl4, while a saturation effect was observed at a high CCl4 concentration. In the presence of excess amounts of styrene, styrene coordinated in an η2-olefinic manner to the niobium center to decrease the reaction rate. No observation of oligomers or polymers of styrene and high stereoselectivity for the radical addition reaction of CCl4 to cyclopentene suggested that the C-C bond formation proceeded inside the coordination sphere of niobium, which was in good accordance with the negative entropy value of the radical addition reaction. Furthermore, reaction of 1a with (bromomethyl)cyclopropane confirmed that both the C-Br bond activation and formation proceeded on the α-diimine-coordinated niobium center during transformation of the cyclopropylmethyl radical to a homoallyl radical. With regard to the reaction mechanism, we detected and isolated NbCl4(α-diimine) (6a) as a transient one-electron oxidized species of 1a during reductive cleavage of the C-X bonds; in addition, the monoanionic α-diimine ligand of 6a adopted a monoanionic canonical form with selective one-electron oxidation of the dianionic ene-diamido form of the ligand in 1a.
Collapse
Affiliation(s)
- Haruka Nishiyama
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka, 5608531, Japan
| | - Hideaki Ikeda
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka, 5608531, Japan
| | - Teruhiko Saito
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka, 5608531, Japan
| | - Benjamin Kriegel
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka, 5608531, Japan
| | - Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka, 5608531, Japan
| | - John Arnold
- Department of Chemistry, University of California , Berkeley, California 94720-1460, United States
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka, 5608531, Japan
| |
Collapse
|
30
|
Sherbow TJ, Fettinger JC, Berben LA. Control of Ligand pK a Values Tunes the Electrocatalytic Dihydrogen Evolution Mechanism in a Redox-Active Aluminum(III) Complex. Inorg Chem 2017; 56:8651-8660. [PMID: 28402654 DOI: 10.1021/acs.inorgchem.7b00230] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Redox-active ligands bring electron- and proton-transfer reactions to main-group coordination chemistry. In this Forum Article, we demonstrate how ligand pKa values can be used in the design of a reaction mechanism for a ligand-based electron- and proton-transfer pathway, where the ligand retains a negative charge and enables dihydrogen evolution. A bis(pyrazolyl)pyridine ligand, iPrPz2P, reacts with 2 equiv of AlCl3 to afford [(iPrPz2P)AlCl2(THF)][AlCl4] (1). A reaction involving two-electron reduction and single-ligand protonation of 1 affords [(iPrHPz2P-)AlCl2] (2), where each of the electron- and proton-transfer events is ligand-centered. Protonation of 2 would formally close a catalytic cycle for dihydrogen production. At -1.26 V versus SCE, in a 0.3 M Bu4NPF6/tetrahydrofuran solution with salicylic acid or (HNEt3)+ as the source of H+, 1 produced dihydrogen electrocatalytically, according to cyclic voltammetry and controlled potential electrolysis experiments. The mechanism for the reaction is most likely two electron-transfer steps followed by two chemical steps based on the available reactivity information. A comparison of this work with our previously reported aluminum complexes of the phenyl-substituted bis(imino)pyridine system (PhI2P) reveals that the pKa values of the N-donor atoms in iPrPz2P are lower, which facilitates reduction before ligand protonation. In contrast, the PhI2P ligand complexes of aluminum are protonated twice before reduction liberates dihydrogen.
Collapse
Affiliation(s)
- Tobias J Sherbow
- Department of Chemistry, University of California , Davis, California 95616, United States
| | - James C Fettinger
- Department of Chemistry, University of California , Davis, California 95616, United States
| | - Louise A Berben
- Department of Chemistry, University of California , Davis, California 95616, United States
| |
Collapse
|
31
|
Xu B, Ma A, Jia T, Hao Z, Gao W, Mu Y. Synthesis and structural characterization of iron complexes bearing N-aryl-phenanthren-o-iminoquinone ligands. Dalton Trans 2016; 45:17966-17973. [PMID: 27781236 DOI: 10.1039/c6dt03572h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Treatments of N-aryl-phenanthren-o-iminoquinone (aryl = 2,6-Me2C6H3 (MeL); 2,6-iPr2C6H3 (iPrL)) with iron powder in THF at 75 °C generate complexes [η2L]2Fe[η1LH] (1a, L = MeL; 1b, L = iPrL) in moderate yields. The X-ray crystallography analysis reveals that the molecule of 1b consists of a Fe(iii) center coordinated by three phenanthren-o-iminosemiquinone ligands, two of which are in an η2 fashion while the remaining one is in an η1 fashion. The analysis of the bond parameters of ligands indicates that the η2-fashioned ligands are radical anions and the η1-fashioned one is in an aminephenolato form. Reactions of MeL and iPrL with FeCl2 in THF produce Fe(iii) complexes [L]2FeCl (2a, L = MeL; 2b, L = iPrL) with the two ligands in the radical anionic form. However, similar reactions of PIQ ligands with FeCl2 in CH2Cl2 yield ion-pair complexes {[L]2FeCl}+[FeCl4]- (3a, L = MeL; 3b, L = iPrL), in which the iron center chelated by two neutral ligands can be formulated as Fe(ii). Reduction of 2b with sodium provides a salt-type complex [iPrL2-]2Fe(ii)Na2 (4), in which a high spin Fe(ii) atom is ligated by two amidophenolate ligands, and the sodium atoms attached to the oxygen atoms of ligands are η3-coordinated by the aryl ring in amido moieties.
Collapse
Affiliation(s)
- Bin Xu
- College of Chemistry, Jilin University, Changchun, China.
| | | | | | | | | | | |
Collapse
|
32
|
Pelties S, Maier T, Herrmann D, de Bruin B, Rebreyend C, Gärtner S, Shenderovich IG, Wolf R. Selective P4
Activation by a Highly Reduced Cobaltate: Synthesis of Dicobalt Tetraphosphido Complexes. Chemistry 2016; 23:6094-6102. [DOI: 10.1002/chem.201603296] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Stefan Pelties
- Institute of Inorganic Chemistry; University of Regensburg; 93040 Regensburg Germany
| | - Thomas Maier
- Institute of Inorganic Chemistry; University of Regensburg; 93040 Regensburg Germany
| | - Dirk Herrmann
- Institute of Inorganic Chemistry; University of Regensburg; 93040 Regensburg Germany
| | - Bas de Bruin
- Van ‘t Hoff Institute for Molecular Sciences; University of Amsterdam; Science Park 904 9747 AG Groningen Netherlands
| | - Christophe Rebreyend
- Van ‘t Hoff Institute for Molecular Sciences; University of Amsterdam; Science Park 904 9747 AG Groningen Netherlands
| | - Stefanie Gärtner
- Institute of Inorganic Chemistry; University of Regensburg; 93040 Regensburg Germany
| | - Ilya G. Shenderovich
- Institute of Inorganic Chemistry; University of Regensburg; 93040 Regensburg Germany
| | - Robert Wolf
- Institute of Inorganic Chemistry; University of Regensburg; 93040 Regensburg Germany
| |
Collapse
|
33
|
Mougel V, Chan KW, Siddiqi G, Kawakita K, Nagae H, Tsurugi H, Mashima K, Safonova O, Copéret C. Low Temperature Activation of Supported Metathesis Catalysts by Organosilicon Reducing Agents. ACS CENTRAL SCIENCE 2016; 2:569-76. [PMID: 27610418 PMCID: PMC4999968 DOI: 10.1021/acscentsci.6b00176] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Indexed: 05/26/2023]
Abstract
Alkene metathesis is a widely and increasingly used reaction in academia and industry because of its efficiency in terms of atom economy and its wide applicability. This reaction is notably responsible for the production of several million tons of propene annually. Such industrial processes rely on inexpensive silica-supported tungsten oxide catalysts, which operate at high temperatures (>350 °C), in contrast with the mild room temperature reaction conditions typically used with the corresponding molecular alkene metathesis homogeneous catalysts. This large difference in the temperature requirements is generally thought to arise from the difficulty in generating active sites (carbenes or metallacyclobutanes) in the classical metal oxide catalysts and prevents broader applicability, notably with functionalized substrates. We report here a low temperature activation process of well-defined metal oxo surface species using organosilicon reductants, which generate a large amount of active species at only 70 °C (0.6 active sites/W). This high activity at low temperature broadens the scope of these catalysts to functionalized substrates. This activation process can also be applied to classical industrial catalysts. We provide evidence for the formation of a metallacyclopentane intermediate and propose how the active species are formed.
Collapse
Affiliation(s)
- Victor Mougel
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir
Prelog Weg 1-5, 8093 Zürich, Switzerland
| | - Ka-Wing Chan
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir
Prelog Weg 1-5, 8093 Zürich, Switzerland
| | - Georges Siddiqi
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir
Prelog Weg 1-5, 8093 Zürich, Switzerland
| | - Kento Kawakita
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3
Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
| | - Haruki Nagae
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3
Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
| | - Hayato Tsurugi
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3
Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3
Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan
| | - Olga Safonova
- Paul
Scherrer Institute, CH-5232 Villigen, Switzerland
| | - Christophe Copéret
- Department
of Chemistry and Applied Biosciences, ETH
Zürich, Vladimir
Prelog Weg 1-5, 8093 Zürich, Switzerland
| |
Collapse
|
34
|
Tanahashi H, Ikeda H, Tsurugi H, Mashima K. Synthesis and Characterization of Paramagnetic Tungsten Imido Complexes Bearing α-Diimine Ligands. Inorg Chem 2016; 55:1446-52. [PMID: 26841126 DOI: 10.1021/acs.inorgchem.5b02145] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tungsten imido complexes bearing a redox-active ligand, such as N,N'-bis(2,6-diisopropylphenyl)-1,4-diaza-2,3-dimethyl-1,3-butadiene (L1), N,N'-bis(2,6-diisopropylphenyl)-1,4-diaza-1,3-butadiene (L2), and 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (L3), were prepared by salt-free reduction of W(═NC6H3-2,6-(i)Pr2)Cl4 (1) using 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene (MBTCD) followed by addition of the corresponding redox-active ligands. In the initial stage, reaction of W(═NC6H3-2,6-(i)Pr2)Cl4 with MBTCD afforded a tetranuclear W(V) imido cluster, [W(═NC6H3-2,6-(i)Pr2)Cl3]4 (2), which served as a unique precursor for introducing redox-active ligands to the tungsten center to give the corresponding mononuclear complexes with a general formula of W(═NC6H3-2,6-(i)Pr2)Cl3(L) (3, L = L1; 4, L = L2; and 6, L = L3). X-ray analyses of complexes 3 and 6 revealed a neutral coordination mode of L1 and L3 to the tungsten in solid state, while the electron paramagnetic resonance (EPR) spectra of 3 and 4 clarified that a radical was predominantly located on the tungsten center supported by neutral L1 or L2, and the EPR spectra of complex 6 indicated that a radical was delocalized over both the tungsten center and the monoanionic redox-active ligand L3.
Collapse
Affiliation(s)
- Hiromasa Tanahashi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka 560-8531, Japan
| | - Hideaki Ikeda
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka 560-8531, Japan
| | - Hayato Tsurugi
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department of Chemistry, Graduate School of Engineering Science, Osaka University , Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
35
|
Mondal P, Das A, Lahiri GK. The Electron-Rich {Ru(acac)2} Directed Varying Configuration of the Deprotonated Indigo and Evidence for Its Bidirectional Noninnocence. Inorg Chem 2016; 55:1208-18. [DOI: 10.1021/acs.inorgchem.5b02409] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Prasenjit Mondal
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Ankita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| |
Collapse
|
36
|
Janes T, Xu M, Song D. Synthesis and reactivity of Li and TaMe3 complexes supported by N,N′-bis(2,6-diisopropylphenyl)-o-phenylenediamido ligands. Dalton Trans 2016; 45:10672-80. [DOI: 10.1039/c6dt01908k] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Redox-active diamido ligands sponsor heterodinuclear TaLi complexes and a TaMe3 species which undergoes photoreduction to yield a Ta(iv) dimer.
Collapse
Affiliation(s)
- Trevor Janes
- Davenport Chemical Research Laboratories
- Department of Chemistry
- University of Toronto
- Toronto
- Canada
| | - Maotong Xu
- Davenport Chemical Research Laboratories
- Department of Chemistry
- University of Toronto
- Toronto
- Canada
| | - Datong Song
- Davenport Chemical Research Laboratories
- Department of Chemistry
- University of Toronto
- Toronto
- Canada
| |
Collapse
|
37
|
Li H, Hall MB. Role of the Chemically Non-Innocent Ligand in the Catalytic Formation of Hydrogen and Carbon Dioxide from Methanol and Water with the Metal as the Spectator. J Am Chem Soc 2015; 137:12330-42. [DOI: 10.1021/jacs.5b07444] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Haixia Li
- Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, United States
| | - Michael B. Hall
- Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, United States
| |
Collapse
|
38
|
Anga S, Naktode K, Adimulam H, Panda TK. Titanium and zirconium complexes of the N,N'-bis(2,6-diisopropylphenyl)-1,4-diaza-butadiene ligand: syntheses, structures and uses in catalytic hydrosilylation reactions. Dalton Trans 2015; 43:14876-88. [PMID: 25177841 DOI: 10.1039/c4dt02013h] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report here a number of dianionic 1,4-diaza-1,3-butadiene complexes of titanium and zirconium synthesised by a salt metathesis reaction. The reaction of either CpTiCl3 or Cp2TiCl2 with the dilithium salt of N,N'-bis(2,6-diisopropylphenyl)-1,4-diaza-1,3-butadiene [; abbreviated (Dipp)2DADLi2] afforded the mono-cyclopentadienyl titanium complex [η(5)-CpTi((Dipp)2DAD)Cl] () bearing a dianionic ene-diamide ligand, while the analogous reaction of zirconocene dichloride (Cp2ZrCl2) with the dilithium salt gave the bis-cyclopentadienyl zirconium complex [Cp2Zr{(Dipp)2DAD}] (). The metal dichloride complexes [Ti((Dipp)2DAD)Cl2] () and [{(Dipp)2DADZrCl(μ-Cl)}2(κ(3)-Cl)(Li)(OEt2)2] () were obtained by the reaction of and anhydrous metal tetrachloride in a 1 : 1 molar ratio in diethyl ether at room temperature. Meanwhile, the homoleptic titanium complex [Ti{((Dipp)2DAD)}2] () was isolated in good yield by the treatment of with TiCl4 in a 1 : 2 molar ratio in diethyl ether. The complexes and were further reacted with neosilyl lithium to afford mono- and bis-alkyl complexes of titanium [η(5)-CpTi{(Dipp)2DAD}(CH2SiMe3)] () and zirconium [Zr{(Dipp)2DAD}(CH2SiMe3)2] () respectively. Molecular structures of the complexes , , and in the solid states were confirmed by single crystal X-ray diffraction analysis. The solid state structures of all the complexes reveal that the metal ions are chelated through the amido-nitrogen atoms and the olefinic carbons of the [(Dipp)2DAD](2-) moiety, satisfying the σ(2),π coordination mode. Compound was used as a catalyst for the intermolecular hydrosilylation reaction of a number of olefins, and moderate activity of catalyst was observed.
Collapse
Affiliation(s)
- Srinivas Anga
- Department of Chemistry, Indian Institute of Technology Hyderabad, Ordnance Factory Estate, Yeddumailaram 502205, Telangana State, India.
| | | | | | | |
Collapse
|
39
|
Saito T, Nishiyama H, Kawakita K, Nechayev M, Kriegel B, Tsurugi H, Arnold J, Mashima K. Reduction of ((t)BuN═)NbCl3(py)2 in a Salt-Free Manner for Generating Nb(IV) Dinuclear Complexes and Their Reactivity toward Benzo[c]cinnoline. Inorg Chem 2015; 54:6004-9. [PMID: 26017157 DOI: 10.1021/acs.inorgchem.5b00812] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The organosilicon reducing reagent 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (1a) was used for the one-electron, salt-free reduction of ((t)BuN═)NbCl3(py)2 (2), resulting in the formation of a neutral, triply chloride-bridged dinuclear niobium(IV) complex, [((t)BuN═)ClNb(py)](μ-Cl)3[((t)BuN═)Nb(py)2] (3) in moderately high yield. Heating 3 in toluene at 80 °C caused a unique intramolecular rearrangement of 3 to another neutral dinuclear complex, [Cl2Nb(py)](μ-Cl)(μ-N(t)Bu)2[ClNb(py)2] (4), in which two niobium(IV) atoms were bridged by one chloride atom and two imido ligands. Reaction of complex 3 with benzo[c]cinnoline produced a benzo[c]cinnoline-bridged dinuclear niobium(V) complex 7 by an overall two-electron reduction of benzo[c]cinnoline through a disproportionation of 3 into a mixture of a niobium(V) complex 2 and a niobium(III) complex, the latter of which efficiently reduced benzo[c]cinnoline.
Collapse
Affiliation(s)
- Teruhiko Saito
- †Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Haruka Nishiyama
- †Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kento Kawakita
- †Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Michael Nechayev
- ‡Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Benjamin Kriegel
- ‡Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Hayato Tsurugi
- †Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - John Arnold
- ‡Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Kazushi Mashima
- †Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
40
|
Satoh Y, Obora Y. Niobium Complexes in Organic Transformations: From Stoichiometric Reactions to Catalytic [2+2+2] Cycloaddition Reactions. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500358] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
41
|
Frey G, Hausmann JN, Streuff J. Titanium-catalyzed reductive umpolung reactions with a metal-free terminal reducing agent. Chemistry 2015; 21:5693-6. [PMID: 25712472 DOI: 10.1002/chem.201500102] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Indexed: 11/07/2022]
Abstract
A new method for titanium-catalyzed reductive umpolung reactions is reported that overcomes the traditional requirement for a stoichiometric metallic reductant. With N,N'-disilylated tetramethyldihydropyrazine as a potent organic reducing agent, reductive carbonyl-nitrile, enone-acrylonitrile and pinacol coupling reactions can be achieved in good yields and stereoselectivities. [Cp2TiI2] is a superior catalyst to [Cp2TiCl2], which is rationalized by a faster generation of the active catalyst [Cp2TiI]. A mechanism is proposed that is in agreement with the experimental results.
Collapse
Affiliation(s)
- Georg Frey
- Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstraße 21, 79104 Freiburg (Germany), Fax: (+49) 761-203-8715
| | | | | |
Collapse
|
42
|
Tanahashi H, Tsurugi H, Mashima K. Synthesis of Alkyl and Alkylidene Complexes of Tungsten Bearing Imido and Redox-Active α-Diimine or o-Iminoquinone Ligands and Their Application as Catalysts for Ring-Opening Metathesis Polymerization of Norbornene. Organometallics 2015. [DOI: 10.1021/om501010n] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Hiromasa Tanahashi
- Department of Chemistry,
Graduate School of Engineering Science, Osaka University and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Hayato Tsurugi
- Department of Chemistry,
Graduate School of Engineering Science, Osaka University and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department of Chemistry,
Graduate School of Engineering Science, Osaka University and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
43
|
Fedushkin IL, Skatova AA, Dodonov VA, Chudakova VA, Bazyakina NL, Piskunov AV, Demeshko SV, Fukin GK. Digallane with Redox-Active Diimine Ligand: Dualism of Electron-Transfer Reactions. Inorg Chem 2014; 53:5159-70. [DOI: 10.1021/ic500259k] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Igor L. Fedushkin
- G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences, Tropinina 49, Nizhny Novgorod 603950, Russian Federation
- Nizhny Novgorod State University, Prospect Gagarina 23, Nizhny Novgorod 603950, Russian Federation
| | - Alexandra A. Skatova
- G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences, Tropinina 49, Nizhny Novgorod 603950, Russian Federation
| | - Vladimir A. Dodonov
- G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences, Tropinina 49, Nizhny Novgorod 603950, Russian Federation
| | - Valentina A. Chudakova
- G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences, Tropinina 49, Nizhny Novgorod 603950, Russian Federation
| | - Natalia L. Bazyakina
- G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences, Tropinina 49, Nizhny Novgorod 603950, Russian Federation
| | - Alexander V. Piskunov
- G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences, Tropinina 49, Nizhny Novgorod 603950, Russian Federation
- Nizhny Novgorod State University, Prospect Gagarina 23, Nizhny Novgorod 603950, Russian Federation
| | - Serhiy V. Demeshko
- Institut für Anorganische Chemie, Georg-August-Universität, Tammannstrasse 4, Göttingen 37077, Germany
| | - Georgy K. Fukin
- G. A. Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences, Tropinina 49, Nizhny Novgorod 603950, Russian Federation
- Nizhny Novgorod State University, Prospect Gagarina 23, Nizhny Novgorod 603950, Russian Federation
| |
Collapse
|
44
|
Mao G, Song Y, Hao T, Li Y, Xu T, Zhang H, Jiang T. Progress in the research of radical anion ligands and their complexes. CHINESE SCIENCE BULLETIN-CHINESE 2014. [DOI: 10.1007/s11434-014-0326-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
45
|
Saito T, Nishiyama H, Tanahashi H, Kawakita K, Tsurugi H, Mashima K. 1,4-Bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadienes as Strong Salt-Free Reductants for Generating Low-Valent Early Transition Metals with Electron-Donating Ligands. J Am Chem Soc 2014; 136:5161-70. [DOI: 10.1021/ja501313s] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Teruhiko Saito
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Haruka Nishiyama
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Hiromasa Tanahashi
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Kento Kawakita
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Hayato Tsurugi
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department
of Chemistry, Graduate School of Engineering Science, Osaka University, and CREST, JST, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
46
|
Petrovskii SK, Saraev VV, Kraikivskii PB, Gurinovich NS, Matveev DA, Bocharova VV. Formation of paramagnetic intermediates under the conditions of Brookhart-type catalyst activation and operation. Russ Chem Bull 2014. [DOI: 10.1007/s11172-013-0186-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
47
|
Chang MC, Dann T, Day DP, Lutz M, Wildgoose GG, Otten E. The Formazanate Ligand as an Electron Reservoir: Bis(Formazanate) Zinc Complexes Isolated in Three Redox States. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201309948] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
48
|
Chang MC, Dann T, Day DP, Lutz M, Wildgoose GG, Otten E. The Formazanate Ligand as an Electron Reservoir: Bis(Formazanate) Zinc Complexes Isolated in Three Redox States. Angew Chem Int Ed Engl 2014; 53:4118-22. [DOI: 10.1002/anie.201309948] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/22/2014] [Indexed: 11/06/2022]
|
49
|
Patra SC, Weyhermüller T, Ghosh P. Ruthenium, Rhodium, Osmium, and Iridium Complexes of Osazones (Osazones = Bis-Arylhydrazones of Glyoxal): Radical versus Nonradical States. Inorg Chem 2014; 53:2427-40. [DOI: 10.1021/ic4022432] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sarat Chandra Patra
- Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 103, West Bengal, India
| | - Thomas Weyhermüller
- Max-Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Prasanta Ghosh
- Department of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 103, West Bengal, India
| |
Collapse
|
50
|
Grupp A, Bubrin M, Ehret F, Kvapilová H, Záliš S, Kaim W. Oxidation and reduction response of α-diimine complexes with tricarbonylrhenium halides and pseudohalides. J Organomet Chem 2014. [DOI: 10.1016/j.jorganchem.2013.08.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|