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Photo-mediated selective deconstructive geminal dihalogenation of trisubstituted alkenes.

ABSTRACT: Selective deconstructive functionalization of alkenes, other than the well-established olefin metathesis and ozonolysis, to produce densely functionalized molecular scaffolds is highly attractive but challenging. Here we report an efficient photo-mediated deconstructive germinal dihalogenation of carbon-carbon double bonds. A wide range of geminal diiodoalkanes and bromo(iodo)alkanes (>40 examples) are directly prepared from various trisubstituted alkenes, including both cyclic and acyclic olefins. This C=C cleavage is highly chemoselective and produces geminal dihalide ketones in good yields. Mechanistic investigations suggest a formation of alkyl hypoiodites from benzyl alcohols and N-iodoimides, which undergo light-induced homolytic cleavage to generate active oxygen radical species.

SUBMITTER: Wang H

PROVIDER: S-EPMC7479597 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Photo-mediated selective deconstructive geminal dihalogenation of trisubstituted alkenes.

Wang Han H Toh Ren Wei RW Shi Xiangcheng X Wang Tonglin T Cong Xu X Wu Jie J

Nature communications 20200908 1

Selective deconstructive functionalization of alkenes, other than the well-established olefin metathesis and ozonolysis, to produce densely functionalized molecular scaffolds is highly attractive but challenging. Here we report an efficient photo-mediated deconstructive germinal dihalogenation of carbon-carbon double bonds. A wide range of geminal diiodoalkanes and bromo(iodo)alkanes (>40 examples) are directly prepared from various trisubstituted alkenes, including both cyclic and acyclic olefi ...[more]

PMID: 32901002

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