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. 2006 May 17;128(19):6314-5.
doi: 10.1021/ja0608139.

Palladium-catalyzed enantioselective C-3 allylation of 3-substituted-1H-indoles using trialkylboranes

Barry M Trost  1 , Jean Quancard
Affiliations

Palladium-catalyzed enantioselective C-3 allylation of 3-substituted-1H-indoles using trialkylboranes

Barry M Trost et al. J Am Chem Soc. .

Abstract

We have developed a new enantioselective C-3 allylation of 3-substituted indoles using allyl alcohol and trialkylboranes. Asymmetric syntheses of 3,3-disubstituted indolines and indolenines in enantiomeric excesses up to 90% have been achieved using the bulky borane 9-BBN-C6H13 as the promoter of the reaction. The dependence of the selectivity on the nature of the borane suggests that the boron reagent has a role beyond promoting ionization of the allyl alcohol. A protocol for oxidation of indolenines to oxindoles has also been developed and led to a formal synthesis of (-)-phenserine.

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Figures

Scheme 1
Scheme 1
Synthesis of (-)-esermethole.
See this image and copyright information in PMC

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