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Mechanistic Perspectives in the Regioselective Indole Addition to Unsymmetrical Silyloxyallyl Cations.

ABSTRACT: Our investigations on the reaction mechanism to account for regioselectivity on the addition of indoles to unsymmetrical silyloxyallyl cations are reported. Using both experimental and computational methods, we confirmed the significance of steric effects from the silyl ether group toward directing the inward approach of indoles, leading to nucleophilic attack at the less substituted electrophilic ?'-carbon. The role of residual water toward accelerating the rate of reaction is established through stabilization of the participating silyloxyallyl cation.

SUBMITTER: Bresnahan CG

PROVIDER: S-EPMC7055495 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Mechanistic Perspectives in the Regioselective Indole Addition to Unsymmetrical Silyloxyallyl Cations.

Bresnahan Caitlin G CG Taylor-Edinbyrd Kiara A KA Cleveland Alexander H AH Malone Joshua A JA Dange Nitin S NS Milet Anne A Kumar Revati R Kartika Rendy R

The Journal of organic chemistry 20190516 11

Our investigations on the reaction mechanism to account for regioselectivity on the addition of indoles to unsymmetrical silyloxyallyl cations are reported. Using both experimental and computational methods, we confirmed the significance of steric effects from the silyl ether group toward directing the inward approach of indoles, leading to nucleophilic attack at the less substituted electrophilic α'-carbon. The role of residual water toward accelerating the rate of reaction is established throu ...[more]

PMID: 31050428

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