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Stereoselective formation of trisubstituted vinyl boronate esters by the acid-mediated elimination of α-hydroxyboronate esters.

ABSTRACT: The copper-catalyzed diboration of ketones followed by an acid-catalyzed elimination leads to the formation of 1,1-disubstituted and trisubstituted vinyl boronate esters with moderate to good yields and selectivity. Addition of tosic acid to the crude diboration products provides the corresponding vinyl boronate esters upon elimination. The trisubstituted vinyl boronate esters are formed as the (Z)-olefin isomer, which was established by subjecting the products to a Suzuki-Miyaura coupling reaction to obtain alkenes of known geometry.

SUBMITTER: Guan W

PROVIDER: S-EPMC4120978 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Stereoselective formation of trisubstituted vinyl boronate esters by the acid-mediated elimination of α-hydroxyboronate esters.

Guan Weiye W Michael Alicia K AK McIntosh Melissa L ML Koren-Selfridge Liza L Scott John P JP Clark Timothy B TB

The Journal of organic chemistry 20140714 15

The copper-catalyzed diboration of ketones followed by an acid-catalyzed elimination leads to the formation of 1,1-disubstituted and trisubstituted vinyl boronate esters with moderate to good yields and selectivity. Addition of tosic acid to the crude diboration products provides the corresponding vinyl boronate esters upon elimination. The trisubstituted vinyl boronate esters are formed as the (Z)-olefin isomer, which was established by subjecting the products to a Suzuki-Miyaura coupling react ...[more]

PMID: 24915498

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