Abstract
[Ir(COE) 2Cl] 2 reacts with Et 3SiH at 23 °C to form a binuclear iridium complex (Et 3Si) 2(H) 2Ir(μ-Cl) 2Ir(H) 2(SiEt 3) 2, 1. Complex 1 reacts further with Et 3SiH at 60 °C to form a second binuclear iridium complex, Et 3Si(H) 2Ir(μ-SiEt 2) 2Ir(H) 2SiEt 3, 2, containing bridging Et 2Si groups. Activation of 2 with H 2 produces trace quantities of a very highly reactive but unobservable species which rapidly and efficiently catalyzes alkyl redistribution reactions of silanes, RR'R''SiH. D 2 and silane exchange experiments establish reactivity features of both 2 and the reactive intermediate. The intermediate cannot be observed, but it is likely a monomeric iridium silyl silylene complex that catalyzes alkyl scrambling via silane exchanges coupled with 1,3-alkyl migrations between silicon centers. DFT calculations support such a mechanism.
Original language | English |
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Pages (from-to) | 307-316 |
Number of pages | 10 |
Journal | ACS Catalysis |
Volume | 2 |
Issue number | 2 |
DOIs | |
State | Published - 3 Feb 2012 |
Externally published | Yes |
Keywords
- 1,3-alkyl migration
- H -triggered catalysis
- bridged silylene complexes
- iridium
- low-T NMR spectroscopy
- redistribution of silanes