Photoinduced Direct Cyanation of C(sp³)–H Bonds

Abstract

A general and practical synthetic protocol for the direct transformation of unreactive C(sp³)–H bonds to C(sp³)–CN bonds has been developed. The homolytic cleavage of the C–H bond is initiated by photo-excited benzophenone, and the resulting carbon radical subsequently reacts with tosyl cyanide to afford the corresponding nitrile in a highly efficient manner. The present methodology is widely applicable to various starting materials including ethers, alcohols, amine derivatives, alkanes, and alkylbenzenes. This newly developed C–H cyanation protocol provides a powerful tool for selective one-carbon elongation for the construction of architecturally complex molecules.

Key words

radical reaction - nitriles - photochemistry - cyanation - C–H functionalizations

• References

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