Kim SM, Yang HS, Eum H, Ha HJ, Yang JW. Mixed Monosilyl Acetals and Catalyst-Dependent Chemoselective Mukaiyama Aldol Reactions.
Chemistry 2017;
23:16432-16437. [PMID:
28940890 DOI:
10.1002/chem.201704456]
[Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Indexed: 11/05/2022]
Abstract
We report a direct, simple, and straightforward approach for the construction of a mixed monosilyl acetal as a new and synthetically valuable functional group by mixing an aldehyde, sodium tert-butoxide, and trimethylsilyl azide. We also demonstrate a catalyst-dependent chemoselective reaction between mixed monosilyl acetals and silyl ketene acetals through Mukaiyama aldol reactions to give different structures of O-protected β-hydroxy esters in excellent yields with high chemoselectivities. This study provided the existence of an oxonium ion intermediate and of its kinetically controlled reaction with the pre-equilibrated silyl enol ether obtained from (E)- and (Z)-isomerization.
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