6142-55-8Relevant academic research and scientific papers
Pushing radical cyclization from regioselective to regiospecific: Cyclization of amidyl radicals controlled by vinylic halogen substitution
Hu, Tianshun,Shen, Meihua,Chen, Qian,Li, Chaozhong
, p. 2647 - 2650 (2007/10/03)
Efficient and regiospecific 6-exo, 7-endo, 7-exo, and even 8-endo amidyl radical cyclizations can be accomplished by the direct reactions of unsaturated N-H amides if they bear a vinylic halogen (Cl, Br, I) substituent. This remarkable halogen-substitution effect could be rationalized in terms of lone pair-lone pair electron repulsion between the N radical and the vinylic halogen atom, in addition to the well-known steric and radical-stabilizing effect.
