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Enantioselective iodolactonization of disubstituted olefinic acids using a bifunctional catalyst.

ABSTRACT: The enantioselective iodolactonizations of a series of diversely substituted olefinic carboxylic acids are promoted by a BINOL-derived, bifunctional catalyst. Reactions involving 5-alkyl- and 5-aryl-4(Z)-pentenoic acids and 6-alkyl- and 6-aryl-5(Z)-hexenoic acids provide the corresponding ?- and ?-lactones having stereogenic C-I bonds in excellent yields and >97:3 er. Significantly, this represents the first organocatalyst that promotes both bromo- and iodolactonization with high enantioselectivities. The potential of this catalyst to induce kinetic resolutions of racemic unsaturated acids is also demonstrated.

SUBMITTER: Fang C

PROVIDER: S-EPMC3528805 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Enantioselective iodolactonization of disubstituted olefinic acids using a bifunctional catalyst.

Fang Chao C Paull Daniel H DH Hethcox J Caleb JC Shugrue Christopher R CR Martin Stephen F SF

Organic letters 20121130 24

The enantioselective iodolactonizations of a series of diversely substituted olefinic carboxylic acids are promoted by a BINOL-derived, bifunctional catalyst. Reactions involving 5-alkyl- and 5-aryl-4(Z)-pentenoic acids and 6-alkyl- and 6-aryl-5(Z)-hexenoic acids provide the corresponding γ- and δ-lactones having stereogenic C-I bonds in excellent yields and >97:3 er. Significantly, this represents the first organocatalyst that promotes both bromo- and iodolactonization with high enantioselectiv ...[more]

PMID: 23199100

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