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The regio- and stereospecific intermolecular dehydrative alkoxylation of allylic alcohols catalyzed by a gold(I) N-heterocyclic carbene complex.

ABSTRACT: A 1:1 mixture of [AuCl(IPr)] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidine) and AgClO(4) catalyzes the intermolecular dehydrative alkoxylation of primary and secondary allylic alcohols with aliphatic primary and secondary alcohols to form allylic ethers. These transformations are regio- and stereospecific with preferential addition of the alcohol nucleophile at the ?-position of the allylic alcohol syn to the departing hydroxyl group and with predominant formation of the E stereoisomer. The minor ? regioisomer is formed predominantly through a secondary reaction manifold involving regioselective ?-alkoxylation of the initially formed allylic ether rather than by the direct ?-alkoxylation of the allylic alcohol.

SUBMITTER: Mukherjee P

PROVIDER: S-EPMC3882269 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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The regio- and stereospecific intermolecular dehydrative alkoxylation of allylic alcohols catalyzed by a gold(I) N-heterocyclic carbene complex.

Mukherjee Paramita P Widenhoefer Ross A RA

Chemistry (Weinheim an der Bergstrasse, Germany) 20130124 10

A 1:1 mixture of [AuCl(IPr)] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidine) and AgClO(4) catalyzes the intermolecular dehydrative alkoxylation of primary and secondary allylic alcohols with aliphatic primary and secondary alcohols to form allylic ethers. These transformations are regio- and stereospecific with preferential addition of the alcohol nucleophile at the γ-position of the allylic alcohol syn to the departing hydroxyl group and with predominant formation of the E stereoisomer ...[more]

PMID: 23348826

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