1
|
Affiliation(s)
- Alexandre J. Sicard
- Department of Chemistry and Biomolecular Science and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - R. Tom Baker
- Department of Chemistry and Biomolecular Science and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| |
Collapse
|
2
|
Yuan J, Bourgeois CJ, Rheingold AL, Hughes RP. Synthesis, structure, and reactivity of iridium perfluorocarbene complexes: regio- and stereo-specific addition of HCl across a metal carbon double bond. Dalton Trans 2015. [PMID: 26211437 DOI: 10.1039/c5dt02275d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Reductive activation of an α-fluorine in the perfluoroalkyl complexes Cp*(L)(i)Ir-CF2RF using Mg/graphite leads to perfluorocarbene complexes Cp*(L)Ir[double bond, length as m-dash]CFRF (L = CO, PMe3; RF = CF3, C2F5, C6F5). New complexes E-Cp*(PMe3)Ir[double bond, length as m-dash]CFC2F5 and E-Cp*(CO)Ir[double bond, length as m-dash]CFC6F5 have been characterized by single crystal X-ray diffraction studies, and a comparison of metric parameters with previously reported analogues is reported. Experimental NMR and computational DFT (B3LYP/LACV3P**++) studies agree that for Ir[double bond, length as m-dash]CFRF complexes (RF = CF3, CF2CF3) the thermodynamic preference for the E or Z isomer depends on the steric requirements of ligand L; when L = CO the Z-isomer (F cis to Cp*) is preferred and for L = PMe3 the E-isomer is preferred. When reduction of the precursors is carried out in the dark the reaction is completely selective to produce E- or Z-isomers. Exposure of solutions of these compounds to ambient light results in slow conversion to a photostationary non-equilibrium mixture of E and Z isomers. In the dark, these E/Z mixtures convert thermally to their preferred E or Z equilibrium geometries in an even slower reaction. A study of the temperature dependent kinetics of this dark transformation allows ΔG(‡)298 for rotation about the Ir[double bond, length as m-dash]CFCF3 double bond to be experimentally determined as 25 kcal mol(-1); a DFT/B3LYP/LACV3P**++ calculation of this rotation barrier is in excellent agreement (27 kcal mol(-1)) with the experimental value. Reaction of HCl with toluene solutions of Cp*(L)Ir[double bond, length as m-dash]CFRF (L = CO, PMe3) or Cp*(CO)Ir[double bond, length as m-dash]C(CF3)2 at low temperature resulted in regiospecific addition of HCl across the metal carbon double bond, ultimately yielding Cp*(L)Ir(CHFRF)Cl and Cp*(CO)Ir[CH(CF3)2]Cl. Reaction of HCl with single E or Z diastereomers of Cp*(L)Ir[double bond, length as m-dash]CFRF gives stereospecific cis-addition to give single diastereomers of Cp*Ir(L)(CHFRF)Cl; addition of HCl to several different E/Z ratios of Cp*(L)Ir[double bond, length as m-dash]CFRF affords ratios of diastereomeric products Cp*(L)Ir(CHFRF)Cl identical to the original ratio of starting material isomers. The addition of HCl is therefore demonstrated to be unambiguously regio- and stereo-specific. The observed product regiochemistry of addition of HCl to Ir[double bond, length as m-dash]CF2, Ir[double bond, length as m-dash]CFRF, and Ir[double bond, length as m-dash]C(CF3)2 ligands is the same and is not dependent on the ground state energy preference (singlet or triplet) for the free perfluorocarbene. DFT calculations on model HCl addition reactions indicate that this regiochemistry is strongly preferred thermodynamically, but predict that in H(δ+)-Cl(δ-) addition to Cp(PH3)Ir[double bond, length as m-dash]CF2, H(δ+) attack at Ir has a lower energy transition state, while for Cp(PH3)Ir[double bond, length as m-dash]CFCF3 and Cp(PH3)Ir[double bond, length as m-dash]C(CF3)2, H(δ+) attack at C is the kinetically preferred pathway. The carbene carbon atoms in Ir[double bond, length as m-dash]CFCF3 and Ir[double bond, length as m-dash]C(CF3)2 complexes are unambiguously basic towards HCl, while in the Ir[double bond, length as m-dash]CF2 analogues the carbene carbon is less basic than its Ir partner, and the eventual regiochemistry of HCl addition arises from thermodynamic control.
Collapse
Affiliation(s)
- Jian Yuan
- Department of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, USA.
| | | | | | | |
Collapse
|
3
|
Andrella NO, Sicard AJ, Gorelsky SI, Korobkov I, Baker RT. A T-shaped Ni[κ 2-(CF 2) 4-] NHC complex: unusual C sp3 -F and M-C F bond functionalization reactions. Chem Sci 2015; 6:6392-6397. [PMID: 30090259 PMCID: PMC6054117 DOI: 10.1039/c5sc01886b] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 07/27/2015] [Indexed: 11/21/2022] Open
Abstract
The reactivity of this T-shaped perfluoronickelacyclopentane–NHC complex with Lewis- and Brønsted acids is enhanced vs. 4-coordinate variants by its low coordination number.
A T-shaped octafluoronickelacyclopentane–NHC complex is prepared and characterized. While the solid-state structure includes a weak isopropyl-CH3 agostic interaction, the reactivity of this complex with Lewis- and Brønsted acids is clearly enhanced by its low coordination number. Reaction with Me3SiOTf, for example, yielded a rare metal–heptafluorocyclobutyl complex whereas carboxylic acids gave substitution at the α-carbon and/or Ni–CF bond protonolysis to afford thermally robust 4H-octafluorobutyl Ni complexes.
Collapse
Affiliation(s)
- Nicholas O Andrella
- Department of Chemistry and Centre for Catalysis Research and Innovation(CCRI) , University of Ottawa , 30 Marie Curie , Ottawa , ON K1N 6N5 Canada
| | - Alexandre J Sicard
- Department of Chemistry and Centre for Catalysis Research and Innovation(CCRI) , University of Ottawa , 30 Marie Curie , Ottawa , ON K1N 6N5 Canada
| | - Serge I Gorelsky
- Department of Chemistry and Centre for Catalysis Research and Innovation(CCRI) , University of Ottawa , 30 Marie Curie , Ottawa , ON K1N 6N5 Canada
| | - Ilia Korobkov
- Department of Chemistry and Centre for Catalysis Research and Innovation(CCRI) , University of Ottawa , 30 Marie Curie , Ottawa , ON K1N 6N5 Canada
| | - R Tom Baker
- Department of Chemistry and Centre for Catalysis Research and Innovation(CCRI) , University of Ottawa , 30 Marie Curie , Ottawa , ON K1N 6N5 Canada
| |
Collapse
|
4
|
Ahrens T, Kohlmann J, Ahrens M, Braun T. Functionalization of fluorinated molecules by transition-metal-mediated C-F bond activation to access fluorinated building blocks. Chem Rev 2014; 115:931-72. [PMID: 25347593 DOI: 10.1021/cr500257c] [Citation(s) in RCA: 609] [Impact Index Per Article: 60.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Theresia Ahrens
- Humboldt-Universität zu Berlin , Department of Chemistry, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | | | | | | |
Collapse
|
5
|
Braun T, Wehmeier F. C–F Bond Activation of Highly Fluorinated Molecules at Rhodium: From Model Reactions to Catalysis. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201001184] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Thomas Braun
- Humboldt‐Universität zu Berlin, Institut für Chemie, Brook‐Taylor‐Str. 2 12489 Berlin, Germany, Fax: +49‐30‐2093‐6966
| | - Falk Wehmeier
- Humboldt‐Universität zu Berlin, Institut für Chemie, Brook‐Taylor‐Str. 2 12489 Berlin, Germany, Fax: +49‐30‐2093‐6966
| |
Collapse
|
6
|
Hughes RP. Fluorine as a ligand substituent in organometallic chemistry: A second chance and a second research career. J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2010.06.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
7
|
Hughes RP. Conversion of Carbon–Fluorine Bonds α to Transition Metal Centers to Carbon–Hydrogen, Carbon–Carbon, and Carbon–Heteroatom Bonds. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900816] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Russell P. Hughes
- Department of Chemistry, Dartmouth College, 6128 Burke Laboratories, Hanover, NH 03755, USA
| |
Collapse
|
8
|
Muzalevskiy VM, Nenajdenko VG, Rulev AY, Ushakov IA, Romanenko GV, Shastin AV, Balenkova ES, Haufe G. Selective synthesis of α-trifluoromethyl-β-aryl enamines or vinylogous guanidinium salts by treatment of β-halo-β-trifluoromethylstyrenes with secondary amines under different conditions. Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.06.048] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
9
|
Huang H, Hurubeanu NR, Bourgeois CJ, Cheah SM, Yuan J, Rheingold AL, Hughes RP. Octahedral perfluoroalkyl complexes of Ir(III) formed by oxidative addition of perfluoroalkyl iodides to Ir(acac)(CO)2. CAN J CHEM 2009. [DOI: 10.1139/v08-114] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Oxidative addition of primary, secondary, or benzylic perfluoroalkyl iodides (RF–I) to the phosphine free Ir(I) precursor Ir(acac)(CO)2 1 (acac = 2,4-pentanedionato) proceeds smoothly to afford octahedral Ir(III) products Ir(acac)(I)(RF)(CO)2, A combination of X-ray crystallographic studies and solution spectroscopy shows that these products are the result of overall trans-addition of the C–I bond to iridium, probably a result of thermodynamic control; evidence for a kinetic product resulting from net cis-addition is obtained in one case. Treatment of the Ir(III) compounds with AgOTf (Tf = CF3SO3) illustrates that the iodo ligand is replaced by triflate with retention of stereochemistry at Ir. The resulting triflate complexes are inert to displacement by H2O or H2. The Ir(III) products exhibit very high CO stretching frequencies in the IR, indicating that the CO ligands may be non-classical. A quantitative estimation of the degree of backbonding to the CO ligands in these compounds, and a comparison of the π-acceptor properties of CO and fluoroalkyl ligands, is made using an approach based on Density Functional Theory (DFT) and Natural Bond Orbital analyses.Key words: iridium, fluoroalkyl, oxidation, carbonyl, DFT.
Collapse
|
10
|
Nova A, Mas-Ballesté R, Ujaque G, González-Duarte P, Lledós A. Csp3–F bond activation by nucleophilic attack of the {Pt2S2} core assisted by non-covalent interactions. Chem Commun (Camb) 2008:3130-2. [DOI: 10.1039/b801889h] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
11
|
Rieth RD, Brennessel WW, Jones WD. Activation of Aromatic, Aliphatic, and Olefinic Carbon–Fluorine Bonds Using Cp*2HfH2. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200600802] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
12
|
Braun T, Noveski D, Ahijado M, Wehmeier F. Hydrodefluorination of pentafluoropyridine at rhodium using dihydrogen: detection of unusual rhodium hydrido complexes. Dalton Trans 2007:3820-5. [PMID: 17712449 DOI: 10.1039/b706846h] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The pentafluoropyridyl complex [Rh(4-C5NF4)(PEt3)3] (3) reacts with H2 to give initially the dihydrido complex cis-mer-[Rh(H)2(4-C5NF4)(PEt3)3] (6). Within a few hours 2,3,5,6-tetrafluoropyridine as well as two rhodium(III) complexes mer-[Rh(H)3(PEt3)3] (mer-) and fac-[Rh(H)3(PEt3)3] (fac-) are formed. A catalytic C-F activation process for the formation of 2,3,5,6-tetrafluoropyridine starting from pentafluoropyridine and dihydrogen using 3 as a catalyst has been developed. Reaction of [RhH(PEt3)3] (1) with hydrogen affords fac-[Rh(H)3(PEt3)3] (fac-7) and mer-[Rh(H)3(PEt3)3] (mer-7) in a ratio of 1 : 7.25 at 193 K. The latter complex represents the first mononuclear rhodium compound bearing trans-hydrides.
Collapse
Affiliation(s)
- Thomas Braun
- Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Strasse 2, 12489 Berlin, Germany.
| | | | | | | |
Collapse
|
13
|
Liu C, Shen DM, Zeng Z, Guo CC, Chen QY. C−F Bond Activation by Modified Sulfinatodehalogenation: Facile Synthesis and Properties of Novel Tetrafluorobenzoporphyrins by Direct Intramolecular Cyclization and Reductive Defluorinative Aromatization of Readily Available β-Perfluoroalkylated Porphyrins. J Org Chem 2006; 71:9772-83. [PMID: 17168596 DOI: 10.1021/jo061743r] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A facile and efficient synthesis of various novel fluorinated extended porphyrins has been developed. The method is based on the direct intramolecular cyclization and reductive defluorinative aromatization of readily available beta-perfluoroalkylated porphyrins by highly selective C-F bond activation under modified sulfinatodehalogenation reaction conditions. Various beta-(omega-chloroperfluoroalkyl)-meso-tetraphenylporphyrins prepared readily by sulfinatodehalogenation reaction or palladium-catalyzed cross-coupling reaction were treated with Na2S2O4/K2CO3 (10:10 equiv per RF tail) in DMSO at 100 degrees C for 10-30 min, resulting in good yields of novel beta-tetrafluorobenzo-meso-tetraphenylporphyrins. That further reduction of C-F bonds of the products was not observed under the optimal conditions indicates the high selectivity of the reaction. It was found that the amount of sodium dithionite, base, and central metal ion of substrate porphyrins play important roles in the reaction. Detailed mechanism investigations and systematic studies on X-ray crystallographic structure and photophysical and electrochemical properties of a series of new tetrafluorobenzoporphyrins are also reported.
Collapse
Affiliation(s)
- Chao Liu
- Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | | | | | | | | |
Collapse
|
14
|
Braun T, Izundu J, Steffen A, Neumann B, Stammler HG. Reactivity of a palladium fluoro complex towards silanes and Bu3SnCHCH2: catalytic derivatisation of pentafluoropyridine based on carbon–fluorine bond activation reactions. Dalton Trans 2006:5118-23. [PMID: 17077884 DOI: 10.1039/b608410a] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The chloro and azido complexes trans-[PdCl(4-C5NF4)(PiPr3)2] (3) and trans-[Pd(N3)(4-C5NF4)(PiPr3)2] (4) can be prepared by reaction of [PdF(4-C5NF4)(PiPr3)2] (2) with Et3SiCl or MeSiN3, respectively. In contrast, reactions of 2 with Ph3SiH or Me2FSiSiFMe2 give the products of reductive elimination 2,3,5,6-tetrafluoropyridine (5) or 4-(fluorodimethylsilyl)tetrafluoropyridine (6) as well as [Pd(PiPr3)2] (1). In a catalytic experiment, pentafluoropyridine can be converted with Ph3SiH into 5 in 62% yield, when 10% of 2 is employed as catalyst. Treatment of trans-[PdF(4-C5NF4)(PiPr3)2] (2) with Bu3SnCH=CH2 in THF at 50 degrees C results in the formation of [Pd(PiPr3)2] (1) and 4-vinyltetrafluoropyridine (7). Complex 2 is also active as a catalyst towards a Stille cross-coupling reaction of pentafluoropyridine with Bu3SnCH=CH2 to give 4-vinyltetrafluoropyridine (7) with a TON of 6. The molecular structure of the complex 3 has been determined by X-ray crystallography.
Collapse
Affiliation(s)
- Thomas Braun
- Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany.
| | | | | | | | | |
Collapse
|
15
|
Bourgeois CJ, Hughes RP, Husebo TL, Smith JM, Guzei IM, Liable-Sands LM, Zakharov LN, Rheingold AL. Reactions of Perfluoroalkyl Iodides with M(C5H5)(CO)(PMe3) [M = Rh, Ir]; Evidence for Direct Fluoroalkylation at a CO Ligand. Organometallics 2005. [DOI: 10.1021/om050714o] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Cheryl J. Bourgeois
- Departments of Chemistry, 6128 Burke Laboratories, Dartmouth College, Hanover New Hampshire 03755, the University of Delaware, Newark, Delaware 19716, and University of California, San Diego, California 92093-0358
| | - Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratories, Dartmouth College, Hanover New Hampshire 03755, the University of Delaware, Newark, Delaware 19716, and University of California, San Diego, California 92093-0358
| | - Trang L. Husebo
- Departments of Chemistry, 6128 Burke Laboratories, Dartmouth College, Hanover New Hampshire 03755, the University of Delaware, Newark, Delaware 19716, and University of California, San Diego, California 92093-0358
| | - Jeremy M. Smith
- Departments of Chemistry, 6128 Burke Laboratories, Dartmouth College, Hanover New Hampshire 03755, the University of Delaware, Newark, Delaware 19716, and University of California, San Diego, California 92093-0358
| | - Ilia M Guzei
- Departments of Chemistry, 6128 Burke Laboratories, Dartmouth College, Hanover New Hampshire 03755, the University of Delaware, Newark, Delaware 19716, and University of California, San Diego, California 92093-0358
| | - Louise M. Liable-Sands
- Departments of Chemistry, 6128 Burke Laboratories, Dartmouth College, Hanover New Hampshire 03755, the University of Delaware, Newark, Delaware 19716, and University of California, San Diego, California 92093-0358
| | - Lev N. Zakharov
- Departments of Chemistry, 6128 Burke Laboratories, Dartmouth College, Hanover New Hampshire 03755, the University of Delaware, Newark, Delaware 19716, and University of California, San Diego, California 92093-0358
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratories, Dartmouth College, Hanover New Hampshire 03755, the University of Delaware, Newark, Delaware 19716, and University of California, San Diego, California 92093-0358
| |
Collapse
|
16
|
Garratt SA, Hughes RP, Kovacik I, Ward AJ, Willemsen S, Zhang D. Carbon−Fluorine Bond Activation Coupled with Carbon−Hydrogen Bond Formation α to Iridium: Kinetics, Mechanism, and Diastereoselectivity. J Am Chem Soc 2005; 127:15585-94. [PMID: 16262424 DOI: 10.1021/ja0545012] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reactions of iridium(fluoroalkyl)hydride complexes CpIr(PMe(3))(CF(2)R(F))Y (R(F) = F, CF(3); Y = H, D) with LutHX (Lut = 2,6-dimethylpyridine; X = Cl, I) results in C-F activation coupled with hydride migration to give CpIr(PMe(3))(CYFR(F))X as variable mixtures of diastereomers. Solution conformations and relative diastereomer configurations of the products have been determined by (19)F{(1)H}HOESY NMR to be (S(C), S(Ir))(R(C), R(Ir)) for the kinetic diastereomer and (R(C), S(Ir))(S(C), R(Ir)) for its thermodynamic counterpart. Isotope labeling experiments using LutDCl/CpIr(PMe(3))(CF(2)R(F))H and CpIr(PMe(3))(CF(2)R(F))D/LutHCl) showed that, unlike a previously studied system, H/D exchange is faster than protonation of the alpha-CF bond, giving an identical mixture of product isotopologues from both reaction mixtures. The kinetic rate law shows a first-order dependence on the concentration of iridium substrate, but a half-order dependence on that of LutHCl; this is interpreted to mean that LutHCl dissociates to give HCl as the active protic source for C-F bond activation. Detailed kinetic studies are reported, which demonstrate that lack of complete diastereoselectivity is not a function of the C-F bond activation/H migration steps but that a cationic intermediate plays a double role in loss of diastereoselectivity; the intermediate can undergo epimerization at iridium before being trapped by halide and can also catalyze the epimerization of kinetic diastereomer product to thermodynamic product. A detailed mechanism is proposed and simulations performed to fit the kinetic data.
Collapse
Affiliation(s)
- Shaun A Garratt
- Department of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, NH 03755, USA
| | | | | | | | | | | |
Collapse
|
17
|
|
18
|
Hughes RP, Laritchev RB, Zakharov LN, Rheingold AL. Unexpected Formation of an Organoplatinum(IV) Fluoride Complex in the Reaction of Pt(TMEDA)(CH3)2 with Perfluoro-sec-butyl Iodide. Organometallics 2005. [DOI: 10.1021/om0504654] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of California, San Diego, California 92093-0358
| | - Roman B. Laritchev
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of California, San Diego, California 92093-0358
| | - Lev N. Zakharov
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of California, San Diego, California 92093-0358
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of California, San Diego, California 92093-0358
| |
Collapse
|
19
|
Hughes RP, Laritchev RB, Zakharov LN, Rheingold AL. Carbon−Fluorine Bond Activation Coupled with Carbon−Carbon Bond Formation at Iridium. Confirmation of Complete Kinetic Diastereoselectivity at the New Carbon Stereocenter by Intramolecular Trapping Using Vinyl as the Migrating Group. J Am Chem Soc 2005; 127:6325-34. [PMID: 15853339 DOI: 10.1021/ja042345d] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The iridium(perfluoropropyl)(vinyl) complex CpIr(PMe(3))(n-C(3)F(7))(CH=CH(2)) (5) has been prepared. It has been characterized by X-ray crystallography, and its ground state conformation in solution has been determined by (19)F{(1)H} HOESY NMR studies. It reacts with the weak acid lutidinium iodide to afford the eta(1)-allylic complex CpIr(PMe(3))((Z)-CH(2)CH=CFC(2)F(5))I (6), which has also been characterized crystallographically. The mechanism of C-F bond activation and C-C bond formation leading to 6 has been elucidated in detail by studying the reaction of 5 with lutidinium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate [LutH(+)B(ArF)(4)(-)], containing a weakly coordinating counteranion. The main kinetic product of this reaction, determined by (19)F{(1)H} HOESY studies at -50 degrees C, is the endo-CpIr(PMe(3))(anti-eta(3)-CH(2)CHCFCF(2)CF(3))[B(ArF)(4)] diastereomer 9, along with a small amount of the exo-syn-isomer 8. Isomer 9 rearranges at -20 degrees C to its exo-anti isomer 7, and subsequently to the thermodynamically favored exo-syn-isomer 8, which has been isolated and crystallographically characterized. Complex 8 reacts with iodide to afford complex6. On the basis of the unambiguously defined kinetically controlled stereochemistry of 9 and 8, a detailed mechanism for the C-F activation/C-C coupling reaction is proposed, the principal conclusion of which is that C-F activation is completely diastereoselective.
Collapse
Affiliation(s)
- Russell P Hughes
- Department of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, USA.
| | | | | | | |
Collapse
|
20
|
Zhang J, Gunnoe TB, Petersen JL. Reactions of (PCP)Ru(CO)(NHPh)(PMe3) (PCP = 2,6-(CH2PtBu2)2C6H3) with Substrates That Possess Polar Bonds. Inorg Chem 2005; 44:2895-907. [PMID: 15819577 DOI: 10.1021/ic0483592] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Ru(II) amido complex (PCP)Ru(CO)(PMe(3))(NHPh) (1) (PCP = 2,6-(CH(2)P(t)Bu(2))(2)C(6)H(3)) reacts with compounds that possess polar C=N, C triple bond N, or C=O bonds (e.g., nitriles, carbodiimides, or isocyanates) to produce four-membered heterometallacycles that result from nucleophilic addition of the amido nitrogen to an unsaturated carbon of the organic substrate. Based on studies of the reaction of complex 1 with acetonitrile, the transformations are suggested to proceed by dissociation of trimethylphosphine, followed by coordination of the organic substrate and then intramolecular N-C bond formation. In the presence of ROH (R = H or Me), the fluorinated amidinate complex (PCP)Ru(CO)(N(Ph)C(C(6)F(5))NH) (6) reacts with excess pentafluorobenzonitrile to produce (PCP)Ru(CO)(F)(N(H)C(C(6)F(5))NHPh) (7). The reaction with MeOH also produces o-MeOC(6)F(4)CN (>90%) and p-MeOC(6)F(4)CN (<10%). Details of the solid-state structures of (PCP)Ru(CO)(F)(N(H)C(C(6)F(5))NHPh) (7), (PCP)Ru(CO)[PhNC{NH(hx)}N(hx)] (8), (PCP)Ru(CO){N(Ph)C(NHPh)O} (9), and (PCP)Ru(CO){OC(Ph)N(Ph)} (10) are reported.
Collapse
Affiliation(s)
- Jubo Zhang
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | | | | |
Collapse
|
21
|
Burling S, Elliott PIP, Jasim NA, Lindup RJ, McKenna J, Perutz RN, Archibald SJ, Whitwood AC. C–F Bond activation at Ni(0) and simple reactions of square planar Ni(ii) fluoride complexes. Dalton Trans 2005:3686-95. [PMID: 16258621 DOI: 10.1039/b510052f] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of Ni(COD)(2)(COD = 1,5-cyclooctadiene) with triethylphosphine and pentafluoropyridine in hexane has been shown previously to yield trans-[NiF(2-C(5)NF(4))(PEt(3))(2)](1a) with a preference for reaction at the 2-position of the heteroaromatic. The corresponding reaction with 2,3,5,6-tetrafluoropyridine was shown to yield trans-[NiF(2-C(5)NF(3)H)(PEt(3))(2)](1b). In this paper, we show that reaction of Ni(COD)(2) with triethylphosphine and pentafluoropyridine in THF yields a mixture of 1a and 1b. Competition reactions of Ni(COD)(2) with triethylphosphine in the presence of mixtures of heteroaromatics in hexane reveal a kinetic preference of k(pentafluoropyridine):k(2,3,5,6-tetrafluoropyridine)= 5.4:1. Treatment of 1a and 1b with Me(3)SiN(3) affords trans-[Ni(N(3))(2-C(5)NF(4))(PEt(3))(2)](2a) and trans-[Ni(N(3))(2-C(5)NHF(3))(PEt(3))(2)](2b), respectively. The complex trans-[Ni(NCO)(2-C(5)NHF(3))(PEt(3))(2)](3b) is obtained on reaction of with Me(3)SiNCO and by photolysis of under CO, while trans-[Ni(eta(1)-C [triple bond CPh)(2-C(5)NF(4))(PEt(3))(2)](4a) is obtained by reaction of phenylacetylene with 1a. Addition of KCN, KI and NaOAc to complex 1a affords trans-[Ni(X)(2-C(5)NF(4))(PEt(3))(2)](5a X = CN, 6a X = I, 7a X = OAc), respectively. The PEt(3) groups of complex are readily replaced by addition of 1,2-bis(dicyclohexylphosphino)ethane (dcpe) to produce [NiF(2-C(5)F(4)N)(dcpe)](8a). Addition of dcpe to trans-[Ni(OTf)(2-C(5)F(4)N)(PEt(3))(2)](10a), however, yields the salt [Ni(2-C(5)F(4)N)(dcpe)(PEt(3))](OTf)(9a) by substitution of only one PEt(3) and displacement of the triflate ligand. The structures of 2b, 4a, 7a and 8a were determined by X-ray crystallography. The influence of different ancillary ligands on the bond lengths and angles of square-planar nickel structures with polyfluoropyridyl ligands is analysed.
Collapse
Affiliation(s)
- Suzanne Burling
- Department of Chemistry, University of York, Heslington, York, UK
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Renkema KB, Werner-Zwanziger U, Pagel MD, Caulton KG. Room-temperature hydrosilylation of the CF bond of vinyl fluoride catalyzed by osmium hydrides. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.molcata.2004.07.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
23
|
Hughes RP, Zhang D, Ward AJ, Zakharov LN, Rheingold AL. Conformational Analysis and Assignments of Relative Stereocenter Configurations in Fluoroalkyl−Iridium Complexes Using 19F{1H} HOESY Experiments. Comparison with Solid-State X-ray Structural Results. J Am Chem Soc 2004; 126:6169-78. [PMID: 15137782 DOI: 10.1021/ja049225q] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Solution conformations about the metal-carbon bond of the secondary fluoroalkyl ligands in iridium complexes [IrCp(PMe(3))(R(F))X] [Cp* = C(5)Me(5); R(F) = CF(CF(3))(2), X = I (1), CH(3) (2); R(F) = CF(CF(3))(CF(2)CF(3)), X = I (4), CH(3) (5)] have been determined using (19)F[(1)H] HOESY techniques. The molecules adopt the staggered conformation with the tertiary fluorine in the more hindered sector between the PMe(3) and X ligands, with CF(3) (and CF(2)CF(3)) substituents lying in the less hindered regions between PMe(3) and Cp or X and Cp. In molecules containing the CF(CF(3))(2) ligand, these conformations are identical to those adopted in the solid state. For compound 4, containing the CF(CF(3))(CF(2)CF(3)) ligand, two diastereomers are observed in solution. Solution conformations and relative stereocenter configuration assignments have been obtained using (19)F[(1)H] HOESY and correlated with the X-ray structure for the major diastereomer of 4, which has the (S(Ir), S(C)) or (R(Ir), R(C)) configuration. Relative stereocenter configurations of analogue 5, for which no suitable crystals could be obtained, were assigned using (19)F[(1)H] HOESY and proved to be different from 4, with 5 preferring the (S(Ir), R(C)) or (R(Ir), S(C)) configuration.
Collapse
Affiliation(s)
- Russell P Hughes
- Department of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, USA.
| | | | | | | | | |
Collapse
|
24
|
Hughes RP, Laritchev RB, Zakharov LN, Rheingold AL. Reductive Activation of Carbon−Fluorine Bonds in Perfluoroalkyl Ligands: An Unexpected Route to the Only Known Tetrafluorobutatriene Transition Metal Complex: Ir(η5-C5Me5)(PMe3)(2,3-η2-CF2CCCF2). J Am Chem Soc 2004; 126:2308-9. [PMID: 14982426 DOI: 10.1021/ja031598o] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Six-electron reduction of the perfluoro-sec-butyl ligand in Cp*Ir(PMe3)I(C4F9) with sodium naphthalenide affords the first known example of a transition metal complex of tetrafluorobutatriene, Cp*Ir(PMe3)(C4F4). The free ligand is a highly unstable compound. The compound has been completely characterized by a single-crystal X-ray diffraction study; the center coordinated double bond shows significant elongation, and the flanking fluoroalkenes show significant shortening, as compared to the dimensions in the free ligand.
Collapse
Affiliation(s)
- Russell P Hughes
- Department of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755,USA.
| | | | | | | |
Collapse
|
25
|
Noveski D, Braun T, Neumann B, Stammler A, Stammler HG. C–F or C–H bond activation and C–C coupling reactions of fluorinated pyridines at rhodium: synthesis, structure and reactivity of a variety of tetrafluoropyridyl complexes. Dalton Trans 2004:4106-19. [PMID: 15573161 DOI: 10.1039/b414734k] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reactions of [RhH(PEt3)3] (1) or [RhH(PEt3)4] (2) with pentafluoropyridine or 2,3,5,6-tetrafluoropyridine afford the activation product [Rh(4-C5NF4)(PEt3)3] (3). Treatment of 3 with CO, 13CO or CNtBu effects the formation of trans-[Rh(4-C5NF4)(CO)(PEt3)2] (4a), trans-[Rh(4-C5NF4)(13CO)(PEt3)2] (4b) and trans-[Rh(4-C5NF4)(CNtBu)(PEt3)2] (5). The rhodium(III) compounds trans-[RhI(CH3)(4-C5NF4)(PEt3)2] (6a) and trans-[RhI(13CH3)(4-C5NF4)(PEt3)2] (6b) are accessible on reaction of 3 with CH3I or 13CH3I. In the presence of CO or 13CO these complexes convert into trans-[RhI(CH3)(4-C5NF4)(CO)(PEt3)2] (7a), trans-[RhI(13CH3)(4-C5NF4)(CO)(PEt3)2] (7b) and trans-[RhI(13CH3)(4-C5NF4)(13CO)(PEt3)2] (7c). The trans arrangement of the carbonyl and methyl ligand in 7a-7c has been confirmed by the 13C-13C coupling constant in the 13C NMR spectrum of 7c. A reaction of 4a or 4b with CH3I or 13CH3I yields the acyl compounds trans-[RhI(COCH3)(4-C5NF4)(PEt3)2] (8a) and trans-[RhI(13CO13CH3)(4-C5NF4)(PEt3)2] (8b), respectively. Complex 8a slowly reacts with more CH3I to give [PEt3Me][Rh(I)2(COCH3)(4-C5NF4)(PEt3)](9). On heating a solution of 7a, the complex trans-[RhI(CO)(PEt3)2] (10) and the C-C coupled product 4-methyltetrafluoropyridine (11) have been obtained. Complex 8a also forms 10 at elevated temperatures in the presence of CO together with the new ketone 4-acetyltetrafluoropyridine (12). The structures of the complexes 3, 4a, 5, 6a, 8a and 9 have been determined by X-ray crystallography. 19F-1H HMQC NMR solution spectra of 6a and 8a reveal a close contact of the methyl groups in the phosphine to the methyl or acyl ligand bound at rhodium.
Collapse
Affiliation(s)
- Daniel Noveski
- Fakultät fur Chemie, Universität Bielefeld, Postfach 100131, 33501, Bielefeld, Germany
| | | | | | | | | |
Collapse
|
26
|
KUBAS GREGORYJ. HETEROLYTIC SPLITTING OF HH, SiH, AND OTHER σ BONDS ON ELECTROPHILIC METAL CENTERS. ADVANCES IN INORGANIC CHEMISTRY 2004. [DOI: 10.1016/s0898-8838(04)56005-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
27
|
Hughes RP, Ward AJ, Rheingold AL, Zakharov LN. Synthesis and molecular structures of platinum(II) and platinum(IV) diimine complexes possessing fluoroalkyl ligands. CAN J CHEM 2003. [DOI: 10.1139/v03-117] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A range of Pt-diimine complexes possessing fluoroalkyl and hydrofluoroalkyl ligands were synthesized from the readily prepared [Pt(diimine)Me2] complexes and the appropriate iodofluoroalkane. For complexes with diimine ligands containing substituents in the 2,6-positions of the aryl group, Pt(II) complexes were obtained due to in situ reductive elimination of MeI, while for complexes with diimine ligands of smaller steric demands (possessing substituents in the 3,5-positions or the 4-position), Pt(IV) complexes were obtained. Attempts to convert the Pt(IV) complexes to the desired Pt(II) species via reductive elimination of MeI, methane, or ethane resulted in either no reaction or degradation of the starting complex. Fluoroalkyl(methyl)platinum(II) complexes were then converted to the fluoroalkyliodoplatinum(II) complexes via addition of I2 or by reaction with aq HI. Several complexes have been characterized crystallographically.Key words: fluoroalkyl, organometallic synthesis, structure, platinum.
Collapse
|
28
|
Noveski D, Braun T, Schulte M, Neumann B, Stammler HG. C–F Activation and hydrodefluorination of fluorinated alkenes at rhodium. Dalton Trans 2003. [DOI: 10.1039/b306635e] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
29
|
Braun T, Perutz RN. Routes to fluorinated organic derivatives by nickel mediated C-F activation of heteroaromatics. Chem Commun (Camb) 2002:2749-57. [PMID: 12478732 DOI: 10.1039/b206154f] [Citation(s) in RCA: 205] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New fluorinated azaheterocycles can be synthesised regio- and chemo-selectively via C-F activation of fluorinated precursors at nickel, with subsequent functionalisation and release from the coordination sphere of the metal; the requirements for productive C-F activation are significantly different from those for C-H bond activation.
Collapse
Affiliation(s)
- Thomas Braun
- Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany.
| | | |
Collapse
|
30
|
Ferrando-Miguel G, Gérard H, Eisenstein O, Caulton KG. Vinyl C-F cleavage by Os(H)3Cl(P(i)Pr3)2. Inorg Chem 2002; 41:6440-9. [PMID: 12444789 DOI: 10.1021/ic020365f] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Os(H)(3)ClL(2) (L = P(i)Pr(3)) reacts at 20 degrees C with vinyl fluoride in the time of mixing to produce OsHFCl([triple bond]CCH(3))L(2) and H(2). In a competitive reaction, the liberated H(2) converts vinyl fluoride to C(2)H(4) and HF in a reaction catalyzed by Os(H)(3)ClL(2). A variable-temperature NMR study reveals these reactions proceed through the common intermediate OsHCl(H(2))(H(2)C=CHF)L(2), via OsClF(=CHMe)L(2) and OsHCl(H(2))(C(2)H(4))L(2), all of which are detected. DFT(B3PW91) calculations of the potential energy and free energy at 298 K of possible intermediates show the importance of entropy to account for their thermodynamic accessibility. Calculations of unimolecular C-F cleavage of coordinated C(2)H(3)F confirms the high activation energy of this process. Catalysis by HF is thus suggested to account for the fast observed reactions, and scavenging of HF with NEt(3) changes the product to exclusively Os(H)(2)Cl(CCH(3))L(2). The analogous reaction of Os(H)(3)ClL(2) with H(2)C=CF(2) produces exclusively OsHFCl(=CCH(3))L(2) and HF, and the latter is again suggested to catalyze C-F scission via the observed intermediates Os(H)(2)Cl(CF(2)CH(3))L(2) and OsHCl(=CFMe)L(2).
Collapse
|
31
|
Hughes RP, Zhang D, Zakharov LN, Rheingold AL. Selective Protonation at a C−F Bond in the Presence of an Iridium−Methyl Bond Gives Diastereoselective Carbon−Fluorine Bond Activation and Carbon−Carbon Bond Formation. A New Path to Carbon Stereocenters Bearing Fluorine Atoms. Organometallics 2002. [DOI: 10.1021/om020718i] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Donghui Zhang
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Lev N. Zakharov
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| |
Collapse
|
32
|
Hughes RP, Laritchev RB, Williamson A, Incarvito CD, Zakharov LN, Rheingold AL. Iridium and Rhodium Complexes Containing Fluorinated Phenyl Ligands and Their Transformation to η2-Benzyne Complexes, Including the Parent Benzyne Complex IrCp*(PMe3)(C6H4). Organometallics 2002. [DOI: 10.1021/om0204787] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Roman B. Laritchev
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Alex Williamson
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Christopher D. Incarvito
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Lev N. Zakharov
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| |
Collapse
|
33
|
Hughes RP, Overby JS, Lam KC, Incarvito CD, Rheingold AL. Oxidative addition reaction of perfluoro-n-butyl iodide to (COD)PtMe2 to give (COD)PtMe(nC4F9). Polyhedron 2002. [DOI: 10.1016/s0277-5387(02)01215-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
34
|
Kraft BM, Jones WD. Mechanism of vinylic and allylic carbon-fluorine bond activation of non-perfluorinated olefins using Cp*(2)ZrH(2). J Am Chem Soc 2002; 124:8681-9. [PMID: 12121111 DOI: 10.1021/ja0125568] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cp(2)ZrH(2) (1) (Cp = pentamethylcyclopentadienyl) reacts with vinylic carbon-fluorine bonds of CF(2)=CH(2) and 1,1-difluoromethylenecyclohexane (CF(2)=C(6)H(10)) to afford Cp(2)ZrHF (2) and hydrodefluorinated products. Experimental evidence suggests that an insertion/beta-fluoride elimination mechanism is occurring. Complex 1 reacts with allylic C-F bonds of the olefins, CH(2)=CHCF(3), CH(2)=CHCF(2)CF(2)CF(2)CF(3), and CH(2)=C(CF(3))(2) to give preferentially 2 and CH(3)-CH=CF(2), CH(3)-CH=CF-CF(2)CF(2)CF(3), and CF(2)=C(CF(3))(CH(3)), respectively, by insertion/beta-fluoride elimination. In the reactions of 1 with CH(2)=CHCF(3) and CH(2)=CHCF(2)CF(2)CF(2)CF(3), both primary and secondary alkylzirconium olefin insertion intermediates were observed in the (1)H and (19)F NMR spectra at low temperature. A deuterium labeling study revealed that more than one olefin-dihydride complex is likely to exist prior to olefin insertion. In the presence of excess 1 and H(2), CH(2)=CHCF(3) and CH(2)=CHCF(2)CF(2)CF(2)CF(3) are reduced to propane and (E)-CH(3)CH(2)CF=CFCF(2)CF(3), respectively.
Collapse
Affiliation(s)
- Bradley M Kraft
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
| | | |
Collapse
|
35
|
Hughes RP, Willemsen S, Williamson A, Zhang D. Carbon−Fluorine Bond Hydrogenolysis in Perfluoroethyl−Iridium Complexes To Give HFC-134a Involves Heterolytic Activation of H2. Organometallics 2002. [DOI: 10.1021/om020225d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Russell P. Hughes
- Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, New Hampshire 03755
| | - Stefan Willemsen
- Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, New Hampshire 03755
| | - Alex Williamson
- Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, New Hampshire 03755
| | - Donghui Zhang
- Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, New Hampshire 03755
| |
Collapse
|
36
|
Albietz PJ, Houlis JF, Eisenberg R. Heterolytic activation of hydrogen as a trigger for iridium complex promoted activation of carbon-fluorine bonds. Inorg Chem 2002; 41:2001-3. [PMID: 11952351 DOI: 10.1021/ic025563l] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The cationic iridium(III) complex [IrCF(3)(CO)(dppe)(DIB)][BARF](2) where DIB = o-diiodobenzene, dppe = 1,2-bis(diphenylphosphino)ethane, and BARF = B(3,5-(CF(3))(2)C(6)H(3))(4)(-) undergoes reaction in the presence of dihydrogen to form [IrH(2)(CO)(2)(dppe)](+) as the major product. Through labeling studies and (1)H and (31)P[(1)H] NMR spectroscopies including parahydrogen measurements, it is shown that the reaction involves conversion of the coordinated CF(3) ligand into carbonyl. In this reaction sequence, the initial step is the heterolytic activation of dihydrogen, leading to proton generation which promotes alpha-C-F bond cleavage. Polarization occurs in the final [IrH(2)(CO)(2)(dppe)](+) product by the reaction of H(2) with the Ir(I) species [Ir(CO)(2)(dppe)](+) that is generated in the course of the CF(3) --> CO conversion.
Collapse
Affiliation(s)
- Paul J Albietz
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
| | | | | |
Collapse
|
37
|
Hughes RP, Smith JM, Incarvito CD, Lam KC, Rhatigan B, Rheingold AL. Cationic Iridium−Perfluoroalkyl Complexes with NH3 and PH3 Ligands. Activation of Carbon−Fluorine Bonds by H2S To Give Bis(trifluoromethyl)dithiametallacyclobutane and Bis(trifluoromethyl)trithiametallacyclohexane Complexes. Organometallics 2002. [DOI: 10.1021/om0200407] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Jeremy M. Smith
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Christopher D. Incarvito
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Kin-Chun Lam
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Brian Rhatigan
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| |
Collapse
|
38
|
Hughes RP, Williamson A, Incarvito CD, Rheingold AL. Synthesis and Molecular Structure of a Perfluoroalkyl Complex of Platinum Containing a PCP Pincer Ligand. Organometallics 2001. [DOI: 10.1021/om010569o] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Alex Williamson
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Christopher D. Incarvito
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| |
Collapse
|
39
|
Hughes RP, Williamson A, Sommer RD, Rheingold AL. The first transition metal complex of tetrafluorobenzyne: Ir(eta(5)-C(5)Me(5))(PMe(3))(eta(2)-C(6)F(4)). J Am Chem Soc 2001; 123:7443-4. [PMID: 11472184 DOI: 10.1021/ja010992o] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- R P Hughes
- Departments of Chemistry, 6128 Burke Laboratory Dartmouth College, Hanover, New Hampshire 03755, USA
| | | | | | | |
Collapse
|
40
|
Hughes RP, Sweetser JT, Tawa MD, Williamson A, Incarvito CD, Rhatigan B, Rheingold AL, Rossi G. Synthesis and Molecular Structures of Perfluoro-n-alkyl Complexes of Platinum(II) and Platinum(IV) Containing Tetramethylethylenediamine (TMEDA) or 1,2-Bis(diphenylphosphino)ethane (DPPE) Ligands. Organometallics 2001. [DOI: 10.1021/om010424h] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Joel T. Sweetser
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Mark D. Tawa
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Alex Williamson
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Christopher D. Incarvito
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Brian Rhatigan
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Gene Rossi
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| |
Collapse
|
41
|
Hughes RP, Kovacik I, Lindner DC, Smith JM, Willemsen S, Zhang D, Guzei IA, Rheingold AL. Unusual Reactivity of “Proton Sponge” as a Hydride Donor to Transition Metals: Synthesis and Structural Characterization of Fluoroalkyl(hydrido) Complexes of Iridium(III) and Rhodium(III). Organometallics 2001. [DOI: 10.1021/om0102347] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Ivan Kovacik
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Danielle C. Lindner
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Jeremy M. Smith
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Stefan Willemsen
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Donghui Zhang
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Ilia A. Guzei
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| |
Collapse
|
42
|
Hughes RP, Maddock SM, Guzei IA, Liable-Sands LM, Rheingold AL. Reactions of halofluorocarbons with group 6 complexes M(C(5)H(5))(2)L (M = Mo, W; L = C(2)H(4), CO). Fluoroalkylation at molybdenum and tungsten, and at cyclopentadienyl or ethylene ligands. J Am Chem Soc 2001; 123:3279-88. [PMID: 11457063 DOI: 10.1021/ja003339u] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The molybdenum(II) and tungsten(II) complexes [MCp(2)L] (Cp = eta(5)-cyclopentadienyl; L = C(2)H(4), CO) react with perfluoroalkyl iodides to give a variety of products. The Mo(II) complex [MoCp(2)(C(2)H(4))] reacts with perfluoro-n-butyl iodide or perfluorobenzyl iodide with loss of ethylene to give the first examples of fluoroalkyl complexes of Mo(IV), MoCp(2)(CF(2)CF(2)CF(2)CF(3))I (8) and MoCp(2)(CF(2)C(6)F(5))I (9), one of which (8) has been crystallographically characterized. In contrast, the CO analogue [MoCp(2)(CO)] reacts with perfluorobenzyl iodide without loss of CO to give the crystallographically characterized salt, [MoCp(2)(CF(2)C(6)F(5))(CO)](+)I(-) (10), and the W(II) ethylene precursor [WCp(2)(C(2)H(4))] reacts with perfluorobenzyl iodide without loss of ethylene to afford the salt [WCp(2)(CF(2)C(6)F(5))(C(2)H(4))](+)I(-) (11). These observations demonstrate that the metal-carbon bond is formed first. In further contrast the tungsten precursor [WCp(2)(C(2)H(4))] reacts with perfluoro-n-butyl iodide, perfluoro-iso-propyl iodide, and pentafluorophenyl iodide to give fluoroalkyl- and fluorophenyl-substituted cyclopentadienyl complexes WCp(eta(5)-C(5)H(4)R(F))(H)I (12, R(F) = CF(2)CF(2)CF(2)CF(3); 15, R(F) = CF(CF(3))(2); 16, R(F) = C(6)F(5)); the Mo analogue MoCp(eta(5)-C(5)H(4)R(F))(H)I (14, R(F) = CF(CF(3))(2)) is obtained in similar fashion. The tungsten(IV) hydrido compounds react with iodoform to afford the corresponding diiodides WCp(eta(5)-C(5)H(4)R(F))I(2) (13, R(F) = CF(2)CF(2)CF(2)CF(3); 18, R(F) = CF(CF(3))(2); 19, R(F) = C(6)F(5)), two of which (13 and 19) have been crystallographically characterized. The carbonyl precursors [MCp(2)(CO)] each react with perfluoro-iso-propyl iodide without loss of CO, to afford the exo-fluoroalkylated cyclopentadiene M(II) complexes MCp(eta(4)-C(5)H(5)R(F))(CO)I (21, M = Mo; 22, M = W); the exo-stereochemistry for the fluoroalkyl group is confirmed by an X-ray structural study of 22. The ethylene analogues [MCp(2)(C(2)H(4))] react with perfluoro-tert-butyl iodide to yield the products MCp(2)[(CH(2)CH(2)C(CF(3))(3)]I (25, M = Mo; 26, M = W) resulting from fluoroalkylation at the ethylene ligand. Attempts to provide positive evidence for fluoroalkyl radicals as intermediates in reactions of primary and benzylic substrates were unsuccessful, but trapping experiments with CH(3)OD (to give R(F)D, not R(F)H) indicate that fluoroalkyl anions are the intermediates responsible for ring and ethylene fluoroalkylation in the reactions of secondary and tertiary fluoroalkyl substrates.
Collapse
Affiliation(s)
- R P Hughes
- Department of Chemistry, Burke Chemistry Laboratory, Dartmouth College, Hanover, New Hampshire 03755-3564, USA
| | | | | | | | | |
Collapse
|
43
|
Barrio P, Castarlenas R, Esteruelas MA, Lledós A, Maseras F, Oñate E, Tomàs J. Reactions of a Hexahydride−Osmium Complex with Aromatic Ketones: C−H Activation versus C−F Activation. Organometallics 2001. [DOI: 10.1021/om000844r] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pilar Barrio
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Unitat de Química Física, Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Ricardo Castarlenas
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Unitat de Química Física, Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Miguel A. Esteruelas
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Unitat de Química Física, Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Agustí Lledós
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Unitat de Química Física, Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Feliu Maseras
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Unitat de Química Física, Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Enrique Oñate
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Unitat de Química Física, Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Jaume Tomàs
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Unitat de Química Física, Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| |
Collapse
|
44
|
Hughes RP, Overby JS, Williamson A, Lam KC, Concolino TE, Rheingold AL. Synthesis, Molecular Structures, and Dynamics of Primary and Secondary Fluoroalkyl Complexes of Palladium(II) with Tetramethylethylenediamine (TMEDA) Ligands. Evaluation of the Structural trans-Influences of Methyl and Fluoroalkyl Groups as Ligands within the Same Coordination Sphere. Organometallics 2000. [DOI: 10.1021/om000694k] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Jason S. Overby
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Alex Williamson
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Kin-Chung Lam
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Thomas E. Concolino
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of Delaware, Newark, Delaware 19716
| |
Collapse
|
45
|
|
46
|
|
47
|
|