Visible-Light-Photoexcited Palladium-Catalyzed Silylmethylation of Benzyl Alcohol Derivatives

Dedicated to Prof. Hisashi Yamamoto on the occasion of his 80th birthday.

Abstract

An intramolecular C–H silylmethylation of benzylic alcohol derivatives catalyzed by a visible-light-photoexcited palladium complex was developed. Irradiation of the palladium complex with blue LEDs resulted in efficient activation of a C–I bond, and subsequent intramolecular radical arylation afforded siloxacycle products. Selective protonation or oxidation of the C–Si bond of the cyclized materials afforded ortho-methylated and ortho-hydroxymethylated derivatives of the benzylic alcohol derivatives.

Key words

palladium catalysis - photochemical reaction - silylmethylation - arylation - siloxacycle - C–C bond formation

• References and Notes

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