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Haloboration of internal alkynes with boronium and borenium cations as a route to tetrasubstituted alkenes.

ABSTRACT: Hail boration! 2-Dimethylaminopyridine-ligated dihaloborocations [X2B(2-DMAP)](+) with a strained four-membered boracycle were used for the haloboration of terminal and dialkyl internal alkynes (see scheme). Esterification then provided vinyl boronate esters as useful precursors to tetrasubstituted alkenes. Following mechanistic studies, the scope of the haloboration was expanded simply by variation of the amine. Pin = 2,3-dimethyl-2,3-butanedioxy.

SUBMITTER: Lawson JR

PROVIDER: S-EPMC3749439 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Haloboration of internal alkynes with boronium and borenium cations as a route to tetrasubstituted alkenes.

Lawson James R JR Clark Ewan R ER Cade Ian A IA Solomon Sophia A SA Ingleson Michael J MJ

Angewandte Chemie (International ed. in English) 20130605 29

Hail boration! 2-Dimethylaminopyridine-ligated dihaloborocations [X2B(2-DMAP)](+) with a strained four-membered boracycle were used for the haloboration of terminal and dialkyl internal alkynes (see scheme). Esterification then provided vinyl boronate esters as useful precursors to tetrasubstituted alkenes. Following mechanistic studies, the scope of the haloboration was expanded simply by variation of the amine. Pin = 2,3-dimethyl-2,3-butanedioxy. ...[more]

PMID: 23740843

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