1
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Szlosek R, Marquardt C, Hegen O, Balázs G, Riesinger C, Timoshkin AY, Scheer M. Synthesis of bismuthanyl-substituted monomeric triel hydrides. Chem Sci 2024:d4sc03926b. [PMID: 39184294 PMCID: PMC11342148 DOI: 10.1039/d4sc03926b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2024] [Accepted: 08/09/2024] [Indexed: 08/27/2024] Open
Abstract
The syntheses and characterizations of the first bismuthanylborane monomers stabilized only by a donor in D·BH2Bi(SiMe3)2 (D = DMAP 1a, IDipp 1b, IMe41c; DMAP = 4-dimethylaminopyridine, IDipp = 1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene, IMe4 = 1,3,4,5-tetramethylimidazol-2-ylidene) are presented. All compounds were synthesized by salt metathesis reactions between D·BH2I and KBi(SiMe3)2(THF)0.3 and represent some of the extremely rare compounds featuring a 2c-2e B-Bi bond in a molecular compound. The products display high sensitivity towards air and light and slowly decompose in solution even at -80 °C. By the reaction of IDipp·GaH2(SO3CF3) with KBi(SiMe3)2(THF)0.3, the synthesis of the first bismuthanylgallane IDipp·GaH2Bi(SiMe3)2 (2) stabilized only by a 2-electron donor was possible, as evident from single crystal X-ray structure determination, NMR spectroscopy and mass spectrometry. Computational studies shed light on the stability of the products and the electronic nature of the compounds.
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Affiliation(s)
- Robert Szlosek
- Institute of Inorganic Chemistry, University of Regensburg 93053 Regensburg Germany
| | - Christian Marquardt
- Institute of Inorganic Chemistry, University of Regensburg 93053 Regensburg Germany
| | - Oliver Hegen
- Institute of Inorganic Chemistry, University of Regensburg 93053 Regensburg Germany
| | - Gábor Balázs
- Institute of Inorganic Chemistry, University of Regensburg 93053 Regensburg Germany
| | - Christoph Riesinger
- Institute of Inorganic Chemistry, University of Regensburg 93053 Regensburg Germany
| | - Alexey Y Timoshkin
- Institute of Chemistry, St. Petersburg State University Universitetskaya nab. 7/9 199034 St. Petersburg Russia
| | - Manfred Scheer
- Institute of Inorganic Chemistry, University of Regensburg 93053 Regensburg Germany
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2
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Szlosek R, Niefanger AS, Balázs G, Seidl M, Timoshkin AY, Scheer M. Characterization of the Ligand Properties of Donor-stabilized Pnictogenyltrielanes. Chemistry 2024; 30:e202303603. [PMID: 38131435 DOI: 10.1002/chem.202303603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/15/2023] [Accepted: 12/21/2023] [Indexed: 12/23/2023]
Abstract
A general synthesis and the characterization of novel alkyl-substituted NHC-stabilized pnictogenylboranes NHC ⋅ BH2 ER2 (NHC=N-heterocyclic carbene, E=P, As; R2 =Me2 , Ph2 , t BuH, Cy2 , (SiMe3 )2 ) are reported. These compounds were reacted with Ni(CO)4 to the corresponding complexes of the type [(NHC ⋅ BH2 ER2 )Ni(CO)3 ] to determine their donor strength by Tolman Electronic Parameters (TEPs) and their steric demand as ligands compared to classical phosphines, superbasic phosphines and other commonly applied donor systems. The results show that the NHC-stabilized pnictogenyltrielanes can be considered as being highly basic, while their steric influence depends strongly on the organic residues as well as the donor attached to the {BH2 } moiety. Although weaker than commonly used superbasic phosphines, the donor strength of pnictogenyltrielanes in general can be classified as of similar strength as NHCs. The steric and electronic properties can easily be modified by alkyl substitution as evident from the TEP trends.
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Affiliation(s)
- Robert Szlosek
- Institut für Anorganische Chemie, Universität Regensburg, 93053, Regensburg, Germany
| | | | - Gábor Balázs
- Institut für Anorganische Chemie, Universität Regensburg, 93053, Regensburg, Germany
| | - Michael Seidl
- Institute of General and Theoretical Chemistry, Leopold-Franzens Universität Innsbruck, Innrain 80-82, 6020, Innsbruck, Austria
| | - Alexey Y Timoshkin
- Institute of Chemistry, Saint Petersburg State University, Universitetskaya emb. 7/9, 199034, St. Petersburg, Russia
| | - Manfred Scheer
- Institut für Anorganische Chemie, Universität Regensburg, 93053, Regensburg, Germany
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3
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Huber T, Bauer JO. A Powerful P-N Connection: Preparative Approaches, Reactivity, and Applications of P-Stereogenic Aminophosphines. Chemistry 2023:e202303760. [PMID: 38055219 DOI: 10.1002/chem.202303760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 12/07/2023]
Abstract
For more than five decades, P-stereogenic aminophosphine chalcogenides and boranes have attracted scientific attention and are still in the focus of ongoing research. In the last years, novel transition metal-based synthesis methods have been discovered, in addition to the long-known use of chiral auxiliaries. Enantiomerically pure compounds with N-P+ -X- (X=O, S, BH3 ) motifs served as valuable reactive building blocks to provide new classes of organophosphorus derivatives, thereby preserving the stereochemical information at the phosphorus atom. Over the years, intriguing applications in organocatalysis and transition metal catalysis have been reported for some representatives. Asymmetric reductions of C=C, C=N, and C=O double bonds were feasible with selected P-stereogenic aminophosphine oxides in the presence of hydrogen transfer reagents. P-stereogenic aminophosphine boranes could be easily deprotected and used as ligands for various transition metals to enable catalytic asymmetric hydrogenations of olefins and imines. This review traces the emergence of a synthetically and catalytically powerful functional compound class with phosphorus-centered chirality in its main lines, starting from classical approaches to modern synthesis methods to current applications.
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Affiliation(s)
- Tanja Huber
- Institut für Anorganische Chemie, Fakultät für Chemie und Pharmazie, Universität Regensburg, Universitätsstraße 31, D-93053, Regensburg, Germany
| | - Jonathan O Bauer
- Institut für Anorganische Chemie, Fakultät für Chemie und Pharmazie, Universität Regensburg, Universitätsstraße 31, D-93053, Regensburg, Germany
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4
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Szlosek R, Seidl M, Balázs G, Scheer M. A General Pathway towards NHC ⋅ GaH 2 (OTf) Adducts - The Key for the Synthesis of NHC-Stabilized Cationic 13/15 Chain Compounds of Gallium. Chemistry 2023; 29:e202301752. [PMID: 37401824 DOI: 10.1002/chem.202301752] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/05/2023]
Abstract
A general pathway towards NHC (NHC=N-heterocyclic carbene)-stabilized galliummonotriflates NHC ⋅ GaH2 (OTf) (NHC=IDipp, 1 a; IPr2 Me2 , 1 b; IMes, 1 c; IDipp=1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene, IPr2 Me2 =1,3-bis-(diisopropyl)-4,5-dimethyl-imidazolin-2-ylidene, IMes=1,3-bis(2,4,6-trimethylphenyl)-imidazolin-2-ylidene) is reported. Quantum chemical calculations give detailed insight into the underlying reaction pathway. The obtained NHC ⋅ GaH2 (OTf) compounds were employed in reactions with donor-stabilized pnictogenylboranes to synthesize the elusive cationic parent 13/15/13 chain compounds [IDipp ⋅ GaH2 ER2 E'H2 ⋅ D][OTf] (3 a: D=IDipp, E=P, E'=B, R=H; 3 b: D=NMe3 , E=P, E'=B, R=H, 3 c: D=NMe3 , E=P, E'=B, R=Ph, 3 d: D=IDipp, E=P, E'=Ga, R=H). Supporting computational studies highlight the electronic features of the products.
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Affiliation(s)
- Robert Szlosek
- Institut für Anorganische Chemie, Universität Regensburg, 93053, Regensburg, Germany
| | - Michael Seidl
- Institut für Anorganische Chemie, Universität Regensburg, 93053, Regensburg, Germany
| | - Gábor Balázs
- Institut für Anorganische Chemie, Universität Regensburg, 93053, Regensburg, Germany
| | - Manfred Scheer
- Institut für Anorganische Chemie, Universität Regensburg, 93053, Regensburg, Germany
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5
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Moussa ME, Kahoun T, Marquardt C, Ackermann MT, Hegen O, Seidl M, Timoshkin AY, Virovets AV, Bodensteiner M, Scheer M. Three- and Five-Membered Anionic Chains of Pnictogenylboranes. Chemistry 2023; 29:e202203206. [PMID: 36478481 DOI: 10.1002/chem.202203206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 12/12/2022]
Abstract
An unprecedented family of three- and five-membered substituted anionic derivatives of parent pnictogenylboranes is herein reported. Reacting various combinations of the pnictogenylboranes H2 E'-BH2 -NMe3 (E'=P, As) with pnictogen-based nucleophiles MER1R2 (E=P, As; R1=H, R2=t Bu; R1=R2=Ph; M=Na, K) allows for the isolation of the unsymmetrical products [Na(18-crown-6)][H2 E'-BH2 -EHt Bu] (3: E=E'=P; 4: E=E'=As; 5: E=As, E'=P) and [M(C)][H2 E'-BH2 -EPh2 ] (7: E=E'=P, M=Na, C=18-crown-6; 8: E=E'=As; M=K, C=[2.2.2]cryptand; 9: E=P, E'=As, M=Na, C=[2.2.2]cryptand; 10: E=As, E'=P, M=K, C=[2.2.2]cryptand). [Na(18-crown-6)][H2 As-BH2 -t BuPH-BH3 ] (6) is only accessible by a different pathway, using t BuPH2 , BH3 ⋅ SMe2 and NaNH2 as starting materials. Additionally, the synthesis of symmetrical diphenyl-substituted compounds [M(18-crown-6)][Ph2 E-BH2 -EPh2 ] (11: E=P, M=Na; 12: E=As, M=K) is reported which can be regarded as isostructural inorganic, negatively charged analogs of dppm (1,1-bis(diphenylphosphino)methane) and dpam (1,1-bis(diphenylarsino)methane). Furthermore, an elongation of the pnictogen boron backbone in compounds 3, 7 and 9' (similar compound to 9, stabilized however by 18-crown-6), is attainable by reacting them with the pnictogenylboranes H2 E'-BH2 -NMe3 leading to corresponding five-membered chain-like compounds [Na(18-crown-6)][H2 E-BH2 -R1R2P-BH2 -E'H2 ] (E=E'=P, R1=H, R2=t Bu (13); E=E'=P, R1=R2=Ph (14); E=E'=As, R1=R2=Ph (15); E=P, E'=As, R1=R2=Ph (16)). Finally, the thermodynamics of the reaction pathways were evaluated by quantum chemical computations.
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Affiliation(s)
- Mehdi Elsayed Moussa
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
| | - Tobias Kahoun
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
| | - Christian Marquardt
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
| | - Matthias T Ackermann
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
| | - Oliver Hegen
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
| | - Michael Seidl
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
| | - Alexey Y Timoshkin
- Institute of Chemistry, St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia
| | - Alexander V Virovets
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
| | - Michael Bodensteiner
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
| | - Manfred Scheer
- Institut für Anorganische Chemie der, Universität Regensburg, 93040, Regensburg, Germany
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6
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Lehnfeld F, Hegen O, Balazs G, Timoshkin A, Scheer M. Coordination chemistry of pnictogenylboranes towards group 6 transition metal Lewis acids. Z Anorg Allg Chem 2022. [DOI: 10.1002/zaac.202200265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | | | | | | | - Manfred Scheer
- University of Regensburg Inorganic Chemistry Universitätsstrasse 31 D-93040 Regensburg GERMANY
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7
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Guo T, Li Z, Bi L, Fan L, Zhang P. Recent advances in organic synthesis applying elemental selenium. Tetrahedron 2022. [DOI: 10.1016/j.tet.2022.132752] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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8
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Horký F, Císařová I, Štěpnička P. A Stable Primary Phosphane Oxide and Its Heavier Congeners. Chemistry 2021; 27:1282-1285. [PMID: 32846012 DOI: 10.1002/chem.202003702] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Indexed: 01/05/2023]
Abstract
(Ferrocenylmethyl)phosphane (1) oxidation with hydrogen peroxide, elemental sulfur and grey selenium produced (ferrocenylmethyl)phosphane oxide 1O, sulfide 1S and selenide 1Se, respectively, as the first isolable primary phosphane chalcogenides lacking steric protection. At elevated temperatures, compound 1O disproportionated into 1 and (ferrocenylmethyl)phosphinic acid. In reactions with [(η6 -mes)RuCl2 ]2 , 1O underwent tautomerization into a phosphane complex [(η6 -mes)RuCl2 {FcCH2 PH(OH)-κP}], whereas 1S and 1Se lost their P-bound chalcogen atoms, giving rise to the phosphane complex [(η6 -mes)RuCl2 (FcCH2 PH2 -κP)] (Fc=ferrocenyl, mes=mesitylene). No tautomerization was observed in the reaction of 1O with B(C6 F5 )3 , which instead produced a Lewis pair FcCH2 P(O)H2 -B(C6 F5 )3 . Phosphane oxide 1O added to C=O bonds of aldehydes and ketones and even to cumulenes PhNCE (E=O and S). However, both PH hydrogens were only employed in the reactions with aldehydes and cyanates.
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Affiliation(s)
- Filip Horký
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 128 40, Prague, Czech Republic
| | - Ivana Císařová
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 128 40, Prague, Czech Republic
| | - Petr Štěpnička
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 128 40, Prague, Czech Republic
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9
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Elsayed Moussa M, Marquardt C, Hegen O, Seidl M, Scheer M. A new family of silver( i) complexes stabilised by the phosphanylborane (C 6H 5) 2PBH 2·N(CH 3) 3. NEW J CHEM 2021. [DOI: 10.1039/d0nj01679a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
By the reaction of the phosphanylborane Ph2PBH2·NMe3 with Ag[FAl{OC6F10(C6F5)}3] or Ag[BF4] first Ag(i) coordination compounds stabilized by phosphine-boranes were obtained.
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Affiliation(s)
- Mehdi Elsayed Moussa
- Institut für Anorganische Chemie der Universität Regensburg, 93040 Regensburg, Germany
| | - Christian Marquardt
- Institut für Anorganische Chemie der Universität Regensburg, 93040 Regensburg, Germany
| | - Oliver Hegen
- Institut für Anorganische Chemie der Universität Regensburg, 93040 Regensburg, Germany
| | - Michael Seidl
- Institut für Anorganische Chemie der Universität Regensburg, 93040 Regensburg, Germany
| | - Manfred Scheer
- Institut für Anorganische Chemie der Universität Regensburg, 93040 Regensburg, Germany
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10
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The Coordination Chemistry of the Phosphanylborane (C
6
H
5
)
2
PBH
2
·N(CH
3
)
3
towards Copper(I) Salts. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000330] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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11
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Butlak AV, Kazakov IV, Stauber A, Hegen O, Scheer M, Pomogaeva AV, Timoshkin AY. Thermal Decomposition of Donor‐Stabilized Phosphinoborane PH
2
BH
2
NMe
3
: A Tensimetry Study. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900817] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Alina V. Butlak
- Institute of Chemistry St. Petersburg State University Universitetskaya emb. 7/9 199034 St. Petersburg Russia
| | - Igor V. Kazakov
- Institute of Chemistry St. Petersburg State University Universitetskaya emb. 7/9 199034 St. Petersburg Russia
| | - Andreas Stauber
- Institut für Anorganische Chemie Universität Regensburg 93040 Regensburg Germany
| | - Oliver Hegen
- Institut für Anorganische Chemie Universität Regensburg 93040 Regensburg Germany
| | - Manfred Scheer
- Institut für Anorganische Chemie Universität Regensburg 93040 Regensburg Germany
| | - Anna V. Pomogaeva
- Institute of Chemistry St. Petersburg State University Universitetskaya emb. 7/9 199034 St. Petersburg Russia
| | - Alexey Y. Timoshkin
- Institute of Chemistry St. Petersburg State University Universitetskaya emb. 7/9 199034 St. Petersburg Russia
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12
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Poller MJ, Huber T, Frickel J, Burford N, Karaghiosoff K. Synthesis and investigation of new phosphorus-chalcogen compounds. PHOSPHORUS SULFUR 2019. [DOI: 10.1080/10426507.2018.1540489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- M. J. Poller
- Department of Chemistry, Ludwig-Maximilians-University, Munich, Germany
| | - T. Huber
- Department of Chemistry, Ludwig-Maximilians-University, Munich, Germany
| | - J. Frickel
- Department of Chemistry, Ludwig-Maximilians-University, Munich, Germany
| | - N. Burford
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
| | - K. Karaghiosoff
- Department of Chemistry, Ludwig-Maximilians-University, Munich, Germany
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13
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Pomogaeva AV, Scheer M, Timoshkin AY. Why Do B–P and Al–P Polymers Differ? Structures, Stability, and Electronic Properties of Chain and Ring [H
2
PEH
2
]
n
Oligomers (E=B, Al;
n
=1
–
15). Chemistry 2018; 24:17046-17054. [DOI: 10.1002/chem.201803008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 07/25/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Anna V. Pomogaeva
- Institute of ChemistrySt. Petersburg State University Universitetskaya nab. 7/9 St. Petersburg 199034 Russia
| | - Manfred Scheer
- Institut für Anorganische ChemieUniversität Regensburg 93040 Regensburg Germany
| | - Alexey Y. Timoshkin
- Institute of ChemistrySt. Petersburg State University Universitetskaya nab. 7/9 St. Petersburg 199034 Russia
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14
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Hegen O, Virovets AV, Timoshkin AY, Scheer M. The Lewis-Base-Stabilized Diphenyl-Substituted Arsanylborane: A Versatile Building Block for Arsanylborane Oligomers. Chemistry 2018; 24:16521-16525. [DOI: 10.1002/chem.201804341] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Oliver Hegen
- Institut für Anorganische Chemie; Universität Regensburg; 93040 Regensburg Germany
| | - Alexander V. Virovets
- Institut für Anorganische Chemie; Universität Regensburg; 93040 Regensburg Germany
- Nikolaev Institute of Inorganic Chemistry; Siberian Division of Russian Academy of Sciences, Acad. Lavrentyev Prosp, 3; 630090 Novosibirsk Russia
- Novosibirsk State University; ul. Pirogova, 3 630090 Novosibirsk Russia
| | - Alexey Y. Timoshkin
- Institute of Chemistry; St. Petersburg State University; 199034 Universitetskaya emb. 7/9 St. Petersburg Russia
| | - Manfred Scheer
- Institut für Anorganische Chemie; Universität Regensburg; 93040 Regensburg Germany
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15
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Marquardt C, Kahoun T, Baumann J, Timoshkin AY, Scheer M. Coordination of Boron-centered Lewis Acids by organo
-substituted Phosphanylboranes. Z Anorg Allg Chem 2017. [DOI: 10.1002/zaac.201700219] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Christian Marquardt
- Institut für Anorganische Chemie; Universität Regensburg; 93040 Regensburg Germany
| | - Tobias Kahoun
- Institut für Anorganische Chemie; Universität Regensburg; 93040 Regensburg Germany
| | - Josef Baumann
- Institut für Anorganische Chemie; Universität Regensburg; 93040 Regensburg Germany
| | - Alexey Y. Timoshkin
- Institute of Chemistry; St. Petersburg State University; Universitetskaya emb. 7/9 199034 St. Petersburg Russia
| | - Manfred Scheer
- Institut für Anorganische Chemie; Universität Regensburg; 93040 Regensburg Germany
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