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Regioselective dihalohydration reactions of propargylic alcohols: gold-catalyzed and noncatalyzed reactions.

ABSTRACT: The regioselective conversion of propargylic alcohols into previously unreported ?,?-diiodo-?-hydroxyketones was achieved by treatment with N-iodosuccinimide in the presence of a gold catalyst. The corresponding ?,?-dichloro-?-hydroxyketones were obtained by treatment with trichloroisocyanuric acid in the absence of a catalyst. The latter reaction can be extended to other alkynols. These transformations can be used to prepare potentially useful halogenated building blocks. Preliminary mechanistic studies suggest that the reaction involves participation of the acetonitrile solvent in the formation of a 5-halo-1,3-oxazine intermediate.

SUBMITTER: D'Oyley JM

PROVIDER: S-EPMC4271674 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Regioselective dihalohydration reactions of propargylic alcohols: gold-catalyzed and noncatalyzed reactions.

D'Oyley Jarryl M JM Aliev Abil E AE Sheppard Tom D TD

Angewandte Chemie (International ed. in English) 20140821 40

The regioselective conversion of propargylic alcohols into previously unreported α,α-diiodo-β-hydroxyketones was achieved by treatment with N-iodosuccinimide in the presence of a gold catalyst. The corresponding α,α-dichloro-β-hydroxyketones were obtained by treatment with trichloroisocyanuric acid in the absence of a catalyst. The latter reaction can be extended to other alkynols. These transformations can be used to prepare potentially useful halogenated building blocks. Preliminary mechanisti ...[more]

PMID: 25147077

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