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One-Pot Cannizzaro Cascade Synthesis of ortho-Fused Cycloocta-2,5-dien-1-ones from 2-Bromo(hetero)aryl Aldehydes.

ABSTRACT: An intramolecular Cannizzaro-type hydride transfer to an in?situ prepared allene enables the synthesis of ortho-fused 4-substituted cycloocta-2,5-dien-1-ones with unprecedented technical ease for an eight-ring carboannulation. Various derivatives could be obtained from commercially available (hetero)aryl aldehydes, trimethylsilylacetylene, and simple propargyl chlorides in good yields.

SUBMITTER: Burroughs L

PROVIDER: S-EPMC4581465 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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One-Pot Cannizzaro Cascade Synthesis of ortho-Fused Cycloocta-2,5-dien-1-ones from 2-Bromo(hetero)aryl Aldehydes.

Burroughs Laurence L Eccleshare Lee L Ritchie John J Kulkarni Omkar O Lygo Barry B Woodward Simon S Lewis William W

Angewandte Chemie (International ed. in English) 20150729 36

An intramolecular Cannizzaro-type hydride transfer to an in situ prepared allene enables the synthesis of ortho-fused 4-substituted cycloocta-2,5-dien-1-ones with unprecedented technical ease for an eight-ring carboannulation. Various derivatives could be obtained from commercially available (hetero)aryl aldehydes, trimethylsilylacetylene, and simple propargyl chlorides in good yields. ...[more]

PMID: 26230528

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