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The cyclopropylcarbinyl route to ?-silyl carbocations.

ABSTRACT: The mesylate derivative of cis-1-hydroxymethyl-2-trimethylsilylcyclopropane has been prepared, along with a number of related mesylates and triflates with substituents on the 1-position. These substrates all solvolyze in CD₃CO₂D to give products derived from cyclopropylcarbinyl cations that undergo further rearrangement to give 3-trimethylsilylcyclobutyl cations. These 3-trimethylsilylcyclobutyl cations are stabilized by a long-range rear lobe interaction with the ?-trimethylsilyl group. When the substituent is electron-withdrawing (CF₃, CN, or CO₂CH₃), significant amounts of bicyclobutane products are formed. The bicyclobutanes are a result of ?-trimethylsilyl elimination from the cationic intermediate that has an unusually long calculated Si-C bond. The solvolysis chemistry of mesylate and triflate derivatives of trans-1-hydroxymethyl-2-trimethylsilylcyclopropane and 1-substituted analogs can be quite different since these substrates do not generally lead to 3-trimethylsilylcyclobutyl cations.

SUBMITTER: Creary X

PROVIDER: S-EPMC6664402 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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The cyclopropylcarbinyl route to γ-silyl carbocations.

Creary Xavier X

Beilstein journal of organic chemistry 20190724

The mesylate derivative of cis-1-hydroxymethyl-2-trimethylsilylcyclopropane has been prepared, along with a number of related mesylates and triflates with substituents on the 1-position. These substrates all solvolyze in CD3CO2D to give products derived from cyclopropylcarbinyl cations that undergo further rearrangement to give 3-trimethylsilylcyclobutyl cations. These 3-trimethylsilylcyclobutyl cations are stabilized by a long-range rear lobe interaction with the γ- ...[more]

PMID: 31435448

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