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Preparation of optically active bicyclodihydrosiloles by a radical cascade reaction.

ABSTRACT: Bicyclodihydrosiloles were readily prepared from optically active enyne compounds by a radical cascade reaction triggered by tris(trimethylsilyl)silane ((Me3Si)3SiH). The reaction was initiated by the addition of a silyl radical to an ?,?-unsaturated ester, forming an ?-carbonyl radical that underwent radical cyclization to a terminal alkyne unit. The resulting vinyl radical attacked the silicon atom in an SHi manner to give dihydrosilole. The reaction preferentially formed trans isomers of bicyclosiloles with an approximately 7:3 to 9:1 selectivity.

SUBMITTER: Miyazaki K

PROVIDER: S-EPMC3740799 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Preparation of optically active bicyclodihydrosiloles by a radical cascade reaction.

Miyazaki Koichiro K Yamane Yu Y Yo Ryuichiro R Uno Hidemitsu H Kamimura Akio A

Beilstein journal of organic chemistry 20130704

Bicyclodihydrosiloles were readily prepared from optically active enyne compounds by a radical cascade reaction triggered by tris(trimethylsilyl)silane ((Me3Si)3SiH). The reaction was initiated by the addition of a silyl radical to an α,β-unsaturated ester, forming an α-carbonyl radical that underwent radical cyclization to a terminal alkyne unit. The resulting vinyl radical attacked the silicon atom in an SHi manner to give dihydrosilole. The reaction preferentially formed trans isomers of bicy ...[more]

PMID: 23946827

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