Sakurai allylation reaction mechanism

The undefined mechanism of the aldol-type Mukaiyama and Sakurai allylation reactions arose the discussion and interest in mechanistic studies [143-145]. The proposed mechanism was proved to proceed through the catalytic activation of the aldehyde and its interaction with the silyl ketene acetal or allylsilane producing the intermediate. From that point the investigation is complicated with two possible pathways that lead either to the release of TMS triflate salt and its electrophihc attack on the trityl group in the intermediate or to the intramolecular transfer of the TMS group to the aldolate position resulting in the evolution of the trityl catalyst and the formation of the product (Scheme 51). On this divergence, series of experimental and spectroscopic studies were conducted. 

Bianchini, C., Glendenning, L. Homogeneous catalysis. Mechanisms of the catalytic Mukaiyama aldol and Sakurai allylation reactions. 

Hollis, T. K., Bosnich, B. Homogeneous Catalysis. Mechanisms of the Catalytic Mukaiyama Aldol and Sakurai Allylation Reactions. J. Am. Chem. Soc. 1995, 117, 4570-4581. 

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