Multiple Si-H Bond Activations by (Bu2PCH2CH2PBu2)-Bu-t-Bu-t and (Bu2PCH2PBu2)-Bu-t-Bu-t Di(phosphine) Complexes of Rhodium and Iridium

作者：Fasulo Meg E; Calimano Elisa; Buchanan J Matthew; Tilley T Don^*

来源：Organometallics, 2013, 32(4): 1016-1028.

DOI：10.1021/om300943e

Reactions of the di(tert-butylphosphino)ethane complex (dtbpe)Rh(CH2Ph) with Ph2SiH2 and Et2SiH2 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 (2)J(SiH) values (44.4 and 52.1 Hz). The reaction of (dtbpm)Rh(CH2Ph) (dtbpm = di(tert-butylphosphino)methane) with Mes(2)SiH(2) gave the pseudo-three-coordinate Rh complex (dtbpm)Rh(SiHMes(2)) (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(GeHMes(2)) (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)Mes(2)] (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)Mes(2)] (6) and (dtbpm)Rh[Ge(CMe=CHMe)Mes(2)] (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-kappa Si] (11), and catalytic investigations indicate that both (dtbpm)Rh(CH2Ph) and 11 are competent catalysts for the conversion of TripPhSiH(2) to 5,7-diisopropyl-3-methyl-1phenyl-2,3-dihydro-1H-silaindole. A dtbpm-supported Ir complex, [(dtbpm)IrCl](2), was used to access the dinuclear bridging silylene complexes [(dtbPm)IrH] (mu-SiPh2)(mu-Cl)(2)[(dtbpm)IrH] (12) and [(dtbpm)IrH] (mu-SiMesCl)(mu-Cl)(p-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-kappa Si), in which the dmp substituent has undergone C-H activation.

• 出版日期2013-2-25