Efficient 1, 8-and 1, 9-asymmetric inductions in the Grignard reaction of δ-and ε-keto esters of 1, 1′-binaphthalen-2-ols with an oligoether tether as the 2′-substituent …

M Date, Y Tamai, T Hattori, H Takayama…

Index: Date; Tamai; Hattori; Takayama; Kamikubo; Miyano Journal of the Chemical Society. Perkin Transactions 1, 2001 , # 8 p. 645 - 653

Full Text: HTML

Citation Number: 16

Abstract

Efficient 1, 8-and 1, 9-asymmetric inductions in the Grignard reaction of podand-type δ-(3, 4) and ε-keto esters (5, 6) are achieved in the presence of MgBr2· OEt2 with up to 97 and 82% optical yields, respectively, by using 2′-[3-(2-methoxyethoxy) propoxy]-1, 1′-binaphthalen- 2-ol as the chiral auxiliary. The 1, 8-asymmetric inductive Grignard reaction has been advantageously utilized in the key step of a synthesis of (−)-malyngolide.