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Organocatalytic asymmetric synthesis of Si-stereogenic silacycles.

ABSTRACT: A strong and confined Brønsted acid catalyzed enantioselective cyclization of bis(methallyl)silanes provides enantioenriched Si-stereogenic silacycles. High enantioselectivities of up to 96.5:3.5 er were obtained for a range of bis(methallyl)silanes. NMR and ESI-MS studies reveal that the formation of a covalent adduct irreversibly inhibits turnover. Remarkably, we found that acetic acid as an additive promotes the collapse of this adduct, enabling full turnover. Experimental investigation and density functional theory (DFT) calculations were conducted to elucidate the origin of this phenomenon and the observed enantioselectivity.

SUBMITTER: Han JT

PROVIDER: S-EPMC11239892 | biostudies-literature | 2024 Jul

REPOSITORIES: biostudies-literature

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Organocatalytic asymmetric synthesis of Si-stereogenic silacycles.

Han Jung Tae JT Tsuji Nobuya N Zhou Hui H Leutzsch Markus M List Benjamin B

Nature communications 20240711 1

A strong and confined Brønsted acid catalyzed enantioselective cyclization of bis(methallyl)silanes provides enantioenriched Si-stereogenic silacycles. High enantioselectivities of up to 96.5:3.5 er were obtained for a range of bis(methallyl)silanes. NMR and ESI-MS studies reveal that the formation of a covalent adduct irreversibly inhibits turnover. Remarkably, we found that acetic acid as an additive promotes the collapse of this adduct, enabling full turnover. Experimental investigation and d ...[more]

PMID: 38992000

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