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Stereoselective synthesis of cyclic ethers via the palladium-catalyzed intramolecular addition of alcohols to phosphono allylic carbonates.

ABSTRACT: Cross metathesis of the acrolein-derived phosphono allylic carbonate and hydroxy alkenes using second generation Grubbs catalyst and copper(I) iodide gave the substituted phosphonates in good yield. Stereospecific palladium(0)-catalyzed cyclization gave tetrahydrofuran and tetrahydropyran vinyl phosphonates. Regioselective Wacker oxidation of the vinyl phosphonate gave the beta-keto phosphonate, which underwent HWE reaction with benzaldehyde to yield the unsaturated ketone. The utility of the cross metathesis/cyclization protocol was further demonstrated by a formal synthesis of centrolobine.

SUBMITTER: He A

PROVIDER: S-EPMC2717013 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Stereoselective synthesis of cyclic ethers via the palladium-catalyzed intramolecular addition of alcohols to phosphono allylic carbonates.

He Anyu A Sutivisedsak Nongnuch N Spilling Christopher D CD

Organic letters 20090701 14

Cross metathesis of the acrolein-derived phosphono allylic carbonate and hydroxy alkenes using second generation Grubbs catalyst and copper(I) iodide gave the substituted phosphonates in good yield. Stereospecific palladium(0)-catalyzed cyclization gave tetrahydrofuran and tetrahydropyran vinyl phosphonates. Regioselective Wacker oxidation of the vinyl phosphonate gave the beta-keto phosphonate, which underwent HWE reaction with benzaldehyde to yield the unsaturated ketone. The utility of the cr ...[more]

PMID: 19586068

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