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Synthesis of azasilacyclopentenes and silanols via Huisgen cycloaddition-initiated C-H bond insertion cascades.

ABSTRACT: An unusual transition metal-free cascade reaction of alkynyl carbonazidates was discovered to form azasilacyclopentenes. Mild thermolysis afforded the products via a series of cyclizations, rearrangements, and an α-silyl C-H bond insertion (rather than the more common Wolff rearrangement, 1,2-shift, or β-silyl C-H insertion) to form silacyclopropanes. A mechanistic proposal for the sequence was informed by control experiments and the characterization of reaction intermediates. The substrate scope and post-cascade transformations were also explored.

SUBMITTER: Shih JL

PROVIDER: S-EPMC5637360 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Synthesis of azasilacyclopentenes and silanols via Huisgen cycloaddition-initiated C-H bond insertion cascades.

Shih Jiun-Le JL Jansone-Popova Santa S Huynh Christopher C May Jeremy A JA

Chemical science 20170904 10

An unusual transition metal-free cascade reaction of alkynyl carbonazidates was discovered to form azasilacyclopentenes. Mild thermolysis afforded the products via a series of cyclizations, rearrangements, and an α-silyl C-H bond insertion (rather than the more common Wolff rearrangement, 1,2-shift, or β-silyl C-H insertion) to form silacyclopropanes. A mechanistic proposal for the sequence was informed by control experiments and the characterization of reaction intermediates. The substra ...[more]

PMID: 29147544

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