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Photooxidation of mixed aryl and biarylphosphines.

ABSTRACT: Arylphosphines and dialkylbiarylphosphines react with singlet oxygen to form phosphine oxides and phosphinate esters. For mixed arylphosphines, the most electron-rich aryl group migrates to form the phosphinate, while for dialkylbiarylphosphines migration of the alkyl group occurs. Dialkylbiarylphosphines also yield arene epoxides, especially in electron-rich systems. Phosphinate ester formation is increased at high temperature, while protic solvents increase the yield of epoxide. The product distribution provides evidence for Buchwald's recent conformational model for the aerobic oxidation of dialkylbiarylphosphines.

SUBMITTER: Zhang D

PROVIDER: S-EPMC2892562 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Photooxidation of mixed aryl and biarylphosphines.

Zhang Dong D Celaje Jeff A JA Agua Alon A Doan Chad C Stewart Timothy T Bau Robert R Selke Matthias M

Organic letters 20100701 13

Arylphosphines and dialkylbiarylphosphines react with singlet oxygen to form phosphine oxides and phosphinate esters. For mixed arylphosphines, the most electron-rich aryl group migrates to form the phosphinate, while for dialkylbiarylphosphines migration of the alkyl group occurs. Dialkylbiarylphosphines also yield arene epoxides, especially in electron-rich systems. Phosphinate ester formation is increased at high temperature, while protic solvents increase the yield of epoxide. The product di ...[more]

PMID: 20527907

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