Nickel-Catalyzed Sequential Dehydrogenation and Cyclization of 2-Amino(Nitro)-benzyl Alcohols with Alkyl Alcohols: Synthesis of C-3-Substituted Quinolines

We herein reported a general and efficient Ni-catalyzed protocol for sequential double de-hydrogenative cyclization of 2-amino(nitro)-benzyl alcohols with primary alcohols to C-3-substituted quinolines releasing water and dihydrogen as by products. As a special highlight, late stage functionalization of cholesterol derivative including chemo-selective transformations of citronellol, fatty acid derived oleyl alcohol and long chain C-4-C-14 alkyl alcohols were reported. Initial mechanistic studies including deuterium-labelling experiments were perform to establish the de-hydrogenative cyclization.

Automated summary

In this study, a general and efficient Ni-catalyzed protocol for sequential double de-hydrogenative cyclization was reported, which can convert 2-amino(nitro)-benzyl alcohols with primary alcohols to C-3-substituted quinolines, releasing water and dihydrogen as byproducts. The late stage functionalization of cholesterol derivatives, including chemo-selective transformations of citronellol, fatty acid derived oleyl alcohol, and long chain C-4-C-14 alkyl alcohols, was highlighted. Initial mechanistic studies, including deuterium-labelling experiments, were conducted to establish the de-hydrogenative cyclization.