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Highly Stereospecific Cyclizations of Homoallylic Silanols.

ABSTRACT: We demonstrate that di-tert-butylsilanols are competent nucleophiles for the intramolecular interception of palladium π-allyl species. In these reactions, allyl ethyl carbonates are the best precursors for the formation of palladium π-allyl intermediates, and [(Cinnamyl)PdCl]₂/BINAP is superior to other Pd salt/ligand framework combinations. Our optimized protocol is compatible with a variety of silanol substrates. Importantly, the cyclization is perfectly stereospecific, proceeding via an anti-syn mechanism, which stands in contrast to reported analogous reactions of alcohols and phenols, known to proceed via an anti-anti mechanism. The alkenes in the product dioxasilinanes serve as blank slates for further functionalization.

SUBMITTER: Shinde AH

PROVIDER: S-EPMC10019461 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Highly Stereospecific Cyclizations of Homoallylic Silanols.

Shinde Anand H AH Dhokale Ranjeet A RA Mague Joel T JT Sathyamoorthi Shyam S

The Journal of organic chemistry 20220728 16

We demonstrate that di-tert-butylsilanols are competent nucleophiles for the intramolecular interception of palladium π-allyl species. In these reactions, allyl ethyl carbonates are the best precursors for the formation of palladium π-allyl intermediates, and [(Cinnamyl)PdCl]2/BINAP is superior to other Pd salt/ligand framework combinations. Our optimized protocol is compatible with a variety of silanol substrates. Importantly, the cyclization is perfectly stereospecific, proce ...[more]

PMID: 35901375

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