18676-90-9Relevant articles and documents
Synthesis of germacyclic compounds by cyclization and annulation reactions utilizing in situ generated germyl cations
Arii, Hidekazu,Iwanami, Yaeko,Kawashima, Takayuki,Masuda, Hideki,Matsumoto, Jin,Mochida, Kunio,Nakane, Daisuke,Shiragami, Tsutomu
, p. 1363 - 1370 (2021)
Germyl cations are one of the heavier group 14 element analogues of carbocations and have been extensively studied for their structures, spectroscopic features, and reactivities to various molecules. 4,4′-Di-tert-butyl-2-diphenylgermylbiphenyl (1) was reacted with [Ph3C][B(C6F5)4] in the presence of 2,6-lutidine to produce dibenzogermole 2 in good yield via the Friedel?Crafts-type cyclization of a germyl cation generated in situ at the neighboring benzene ring. This germa-Friedel?Crafts reaction was used to synthesize ladder-type germole 4 and trigermasumanene 6. The emission bands of 2 were red-shifted relative to those of fluorene, which for dibenzosilole are associated with orbital interactions between a heavier group 14 element moiety and a π-conjugated framework, such as σ*?π* conjugation. The following reaction was conducted to demonstrate annulation between an in situ generated germyl cation and alkynes. Benzyldiphenylgermane (7) was treated sequentially with [Ph3C][B(C6F5)4], 2,6-di-tert-butyl-4-methylpyridine, and alkynes to produce 1,2-dihydro-2,2-diphenyl-2-germanaphthalene derivatives 8, together with alkynylgermane 9 in some cases. We compare the products obtained in this study with those obtained from reactions involving an in situ generated silyl cation, which we reported previously.
Multiple Si-H bond activations by tBu2PCH 2CH2PtBu2 and tBu 2PCH2PtBu2 Di(phosphine) complexes of rhodium and iridium
Fasulo, Meg E.,Calimano, Elisa,Buchanan, J. Matthew,Tilley, T. Don
, p. 1016 - 1028 (2013/04/23)
Reactions of the di(tert-butylphosphino)ethane complex (dtbpe)Rh(CH 2Ph) with Ph2SiH2 and Et2SiH 2 resulted in isolation of (dtbpe)Rh(H)2(SiBnPh 2) (1; Bn = CH2Ph) and (dtbpe)Rh(H) 2(SiBnEt2) (2), respectively. Both 1 and 2 feature strong interactions between the rhodium hydride and silyl ligands, as indicated by large 2JSiH values (44.4 and 52.1 Hz). The reaction of (dtbpm)Rh(CH2Ph) (dtbpm = di(tert-butylphosphino)methane) with Mes2SiH2 gave the pseudo-three-coordinate Rh complex (dtbpm)Rh(SiHMes2) (3), which is stabilized in the solid state by agostic interactions between the rhodium center and two C-H bonds of a methyl substituent on the mesityl group. The analogous germanium compound (dtbpm)Rh(GeHMes2) (4) is also accessible. Complex 3 readily undergoes reactions with diphenylacetylene, phenylacetylene, and 2-butyne to give the silaallyl complexes (dtbpm)Rh[Si(CPh=CHPh)Mes2] (5), (dtbpm)Rh[Si(CH=CHPh)Mes2] (7), and (dtbpm)Rh(Si(CMe=CHMe)Mes 2) (8) via net insertions into the Si-H bond. The germaallyl complexes (dtbpm)Rh[Ge(CPh=CHPh)Mes2] (6) and (dtbpm)Rh[Ge(CMe=CHMe) Mes2] (9) were synthesized under identical conditions starting from 4. The reaction of (dtbpm)Rh(CH2Ph) with 1 equiv of TripPhSiH 2 yielded (dtbpm)Rh(H)2[5,7-diisopropyl-3-methyl-1-phenyl- 2,3-dihydro-1H-silaindenyl-κSi] (11), and catalytic investigations indicate that both (dtbpm)Rh(CH2Ph) and 11 are competent catalysts for the conversion of TripPhSiH2 to 5,7-diisopropyl-3-methyl-1- phenyl-2,3-dihydro-1H-silaindole. A dtbpm-supported Ir complex, [(dtbpm)IrCl]2, was used to access the dinuclear bridging silylene complexes [(dtbpm)IrH](μ-SiPh2)(μ-Cl)2[(dtbpm)IrH] (12) and [(dtbpm)IrH](μ-SiMesCl)(μ-Cl)(μ-H)[(dtbpm)IrH] (13). The reaction of [(dtbpm)IrCl]2 with a sterically bulky primary silane, (dmp)SiH3 (dmp = 2,6-dimesitylphenyl), allowed isolation of the mononuclear complex (dtbpm)Ir(H)4(10-chloro-1-mesityl-5,7-dimethyl-9, 10-dihydrosilaphenanthrene-κSi), in which the dmp substituent has undergone C-H activation.
Acceleration of the substitution of silanes with Grignard reagents by using either LiCl or YCl3/MeLi
Hirone, Naoki,Sanjiki, Hiroaki,Tanaka, Ryoichi,Hata, Takeshi,Urabe, Hirokazu
supporting information; experimental part, p. 7762 - 7764 (2010/12/25)
Getting up to speed: Both LiCl and the YCl3/MeLi catalyst system have an acceleration effect upon the substitution of silanes using Grignard reagents (see scheme). The method provides access to benzyl-, allyl-, and arylsilanes in good yields from the starting silanes.
