Palladium(II)-Catalyzed Conjugate Phosphination of Electron-Deficient Acceptors
摘要:
A general protocol for the conjugate transfer of diphenyl-, dicyclohexyl-, and di-tert-butylphosphinyl groups from silylphosphlnes to cyclic and acyclic electron-deficient acceptors employing a bench-stable palladium(II) catalyst Is reported. Several E and Z configured alpha,beta-unsaturated carbonyl and carboxyl acceptors (including imides) as well as nitroalkenes participate in this palladium(II)-catalyzed process in high chemical yields.
rhodium(I) by means of an RhI–OH complex, enables the conjugate transfer of nucleophilic silicon onto α,β-unsaturated acceptors. Pre- or in situ formed cationic rhodium(I)–binap complexescatalyze this novel carbon–silicon bond formation with exceptional enantiocontrol, 92 to >99% ee for cyclic carbonyl and carboxylcompounds as well as >99% ee for acyclic carboxylcompounds.
铑(I)催化的硅-硼键活化,即通过Rh I -OH络合物将硅从硼转变为铑(I),可以将亲核硅共轭转移到α,β上-不饱和受体。预制的或原位形成的阳离子铑(I)-联萘酚配合物可催化这种新型的碳-硅键形成,具有出色的对映体控制能力,环状羰基和羧基化合物的ee为92%至> 99%ee,无环羧基化合物的ee> 99%。
Catalytic Asymmetric CSi Bond Formation to Acyclic α,β-Unsaturated Acceptors by RhI-Catalyzed Conjugate Silyl Transfer Using a SiB Linkage