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Bromoacetate Olefination Protocol for Norbixin and Julia-Kocienski Olefination for Its Ester Syntheses.

ABSTRACT: A new olefination protocol utilizing ethyl bromoacetate was highlighted, in which magnesium enolate of the ester coupled with C₂₀ dialdehyde 6, and double eliminations of the protected hydroxyl groups and bromine atoms of the coupling bromohydrin product, efficiently produced norbixin 1 after concomitant hydrolysis of the ester. A new (C₇ + C₁₀ + C₇) disconnection approach was demonstrated for the synthesis of norbixin ethyl ester 2 by the Julia-Kocienski olefination of novel C₇ benzothiazolyl-sulfone 11 and C₁₀ 2,7-dimethyl-2,4,6-octatrienedial (12).

SUBMITTER: Kim D

PROVIDER: S-EPMC6648602 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Bromoacetate Olefination Protocol for Norbixin and Julia-Kocienski Olefination for Its Ester Syntheses.

Kim Dahye D Alam Mohammad Shariful MS Chung Wook-Jin WJ Koo Sangho S

ACS omega 20190607 6

A new olefination protocol utilizing ethyl bromoacetate was highlighted, in which magnesium enolate of the ester coupled with C20 dialdehyde 6, and double eliminations of the protected hydroxyl groups and bromine atoms of the coupling bromohydrin product, efficiently produced norbixin 1 after concomitant hydrolysis of the ester. A new (C7 + C10 + C7) disconnection approach was demonstrated for the synthesis of norbixin ethyl ester 2</b ...[more]

PMID: 31460094

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