Maust, Mark C. published the artcileSwitchable Regioselective 6-endo or 5-exo Radical Cyclization via Photoredox Catalysis, SDS of cas: 39856-58-1, the publication is Journal of the American Chemical Society (2022), 144(9), 3776-3781, database is CAplus and MEDLINE.
Here a simple method for reagent controlled regioselective radical cyclization of halogenated N-heterocycles onto pendant olefins was developed. Radical generation occurs under mild photoredox conditions with control of the regioselectivity governed by the rate of hydrogen atom transfer (HAT). Utilizing a polarity-matched thiol-based HAT agent promoted the highly selective formation of the 5-exo cyclization product. Conversely, limiting the solubility of the HAT reagent Hantzsch ester (HEH) leads to selective formation of the thermodynamically favored 6-endo product. This occurs through an initial 5-exo cyclization, with the resulting alkyl radical intermediate undergoing neophyl rearrangement to form the 6-endo product. Development of this switchable catalysis strategy allows for two modes of divergent reactivity to form either the 6-endo or 5-exo product, generating fused N-heteroaromatic/saturated ring systems.
Journal of the American Chemical Society published new progress about 39856-58-1. 39856-58-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Bromide,Amine, name is 2-Bromopyridin-3-amine, and the molecular formula is C5H5BrN2, SDS of cas: 39856-58-1.
Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem