Photocatalytic Redox-Neutral C(sp³)–C(sp³) Cleaving Transalkylation of Heteroarenes

In this work, a photocatalytic redox-neutral carbon-carbon bond metathesis and transalkylation of heteroarenes was established. When CBZ6 was used as the photocatalyst, alkyl migration from 2-alkyl pyrrolidines or piperidines to heteroaryl nitriles occurred, affording heteroaryl-substituted tertiary alkyl ethers in up to 98% yields. The cyanyl groups released from nitrites are trapped by alkyl donors to form 2-cyano pyrrolidines or piperidines. These nitriles can be recycled for the regeneration of alkyl donors. A wide range of substrates has been proven to be suitable. Preliminary mechanistic investigations revealed the photocatalytic nature of this reaction.