Synthesis 2018; 50(11): 2235-2246
DOI: 10.1055/s-0036-1591548
paper
© Georg Thieme Verlag Stuttgart · New York

Copper-Catalyzed Enantioselective Coupling between Allyl­boronates and Phosphates Using a Phenol–Carbene Chiral Ligand: Asymmetric Synthesis of Chiral Branched 1,5-Dienes

Yuto Yasuda
a   Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan   Email: sawamura@sci.hokudai.ac.jp
,
Hirohisa Ohmiya*
b   Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan   Email: ohmiya@p.kanazawa-u.ac.jp
,
Masaya Sawamura*
a   Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan   Email: sawamura@sci.hokudai.ac.jp
› Author Affiliations
This work was supported by Grants-in-Aid for Scientific Research (B) (No. 15H03803), JSPS to H.O. and by CREST and ACT-C, JST to M.S.
Further Information

Publication History

Received: 19 December 2017

Accepted after revision: 12 February 2018

Publication Date:
20 March 2018 (online)


Abstract

Details of the Cu-catalyzed enantioselective allyl–allyl coupling reaction between allylboronates and (Z)-allylic phosphates using a new chiral N-heterocyclic carbene (NHC) ligand containing a phenolic hydroxy group are presented. The copper catalysis delivers enantio­enriched chiral 1,5-dienes with a tertiary stereogenic center. Compatibility with various functional groups and the use of earth-abundant and relatively low-toxicity copper as a metal are attractive features of this protocol. The utility of the chiral phenol–NHC ligand for enantioselective copper catalysis with organoboron compounds is demonstrated and enantiodiscrimination models are discussed.

Supporting Information

 
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