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Alcohol-assisted phosphine catalysis: one-step syntheses of dihydropyrones from aldehydes and allenoates.

ABSTRACT: This paper describes the phosphine-catalyzed annulation of methyl allenoate with various aromatic aldehydes to form 6-aryl-4-methoxy-5,6-dihydro-2-pyrones. In this reaction, the addition of an alcohol was necessary to induce dihydropyrone formation, with the optimal agent being methanol. Moreover, the addition of n-butyllithium suppressed the formation of the noncyclized product, leading to the exclusive isolation of the dihydropyrone. This method provides an efficient, one-step route toward disubstituted dihydropyrones from simple, stable starting materials.

SUBMITTER: Creech GS

PROVIDER: S-EPMC2532593 | biostudies-other | 2008 Feb

REPOSITORIES: biostudies-other

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Alcohol-assisted phosphine catalysis: one-step syntheses of dihydropyrones from aldehydes and allenoates.

Creech Gardner S GS Kwon Ohyun O

Organic letters 20080104 3

This paper describes the phosphine-catalyzed annulation of methyl allenoate with various aromatic aldehydes to form 6-aryl-4-methoxy-5,6-dihydro-2-pyrones. In this reaction, the addition of an alcohol was necessary to induce dihydropyrone formation, with the optimal agent being methanol. Moreover, the addition of n-butyllithium suppressed the formation of the noncyclized product, leading to the exclusive isolation of the dihydropyrone. This method provides an efficient, one-step route toward dis ...[more]

PMID: 18173275

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