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Steric effects compete with aryne distortion to control regioselectivities of nucleophilic additions to 3-silylarynes.

ABSTRACT: We report an experimental and computational study of 3-silylarynes. The addition of nucleophiles yield ortho-substituted products as a result of aryne distortion, but meta-substituted products form predominately when the nucleophile is large. Computations correctly predict the preferred site of attack observed in both nucleophilic addition and cycloaddition experiments. Nucleophilic additions to 3-tert-butylbenzyne, which is not significantly distorted, give meta-substituted products.

SUBMITTER: Bronner SM

PROVIDER: S-EPMC3445038 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Steric effects compete with aryne distortion to control regioselectivities of nucleophilic additions to 3-silylarynes.

Bronner Sarah M SM Mackey Joel L JL Houk K N KN Garg Neil K NK

Journal of the American Chemical Society 20120815 34

We report an experimental and computational study of 3-silylarynes. The addition of nucleophiles yield ortho-substituted products as a result of aryne distortion, but meta-substituted products form predominately when the nucleophile is large. Computations correctly predict the preferred site of attack observed in both nucleophilic addition and cycloaddition experiments. Nucleophilic additions to 3-tert-butylbenzyne, which is not significantly distorted, give meta-substituted products. ...[more]

PMID: 22876797

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