CC BY-ND-NC 4.0 · Synlett 2019; 30(04): 442-448
DOI: 10.1055/s-0037-1611644
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Asymmetric Synthesis of Chiral 1,3-Dimethyl Units Through a Double Michael Reaction of Nitromethane and Crotonaldehyde Catalyzed by Diphenylprolinol Silyl Ether

Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza Aoba, Aoba-ku, Sendai 980-8578, Japan   Email: yhayashi@m.tohoku.ac.jp
,
Shunsuke Toda
› Author Affiliations
JSPS KAKENHI grant number JP18H04641: Hybrid Catalysis for Enabling Molecular Synthesis on Demand, and The Uehara Memorial Foundation.
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Publication History

Received: 30 August 2018

Accepted after revision: 03 December 2018

Publication Date:
16 January 2019 (online)


Published as part of the 30 Years SYNLETT – Pearl Anniversary Issue

Abstract

An efficient synthetic route to install chiral 1,3-dimethyl units through a double Michael reaction of crotonaldehyde and nitromethane catalyzed by diphenylprolinol silyl ether is developed. Either 1,3-syn- or 1,3-anti-dimethyl units are obtained selectively depending on the enantiomer of the diphenylprolinol silyl ether catalyst used. The side chain of pneumocandin B0 is synthesized enantioselectively by using the present method as a key step.

Supporting Information