Ruthenium-Catalyzed Dehydrogenative β-Benzylation of 1,2,3,4-Tetrahydroquinolines with Aryl Aldehydes: Access to Functionalized Quinolines.
A new benzylation protocol, enabling straightforward access to β-benzylated quinolines, has been demonstrated. By employing readily available [RuCl2(p-cymene)]2 as a catalyst and O2 as a sole green oxidant, various 1,2,3,4-tetrahydroquinolines were efficiently converted in combination with aryl aldehydes into desired products in a step- and atom-economic fashion together with the advantages of excellent functional group tolerance and chemoselectivity, offering an important basis for the transformation of saturated N-heterocycles into functionalized N-heteroaromatics via a dehydrogenative cross-coupling strategy. Mechanistic investigations support that the reaction undergoes a monodehydrogenation-triggered β-benzylation mode.
School of Chemistry & Chemical Engineering, South China University of Technology , Wushan Road - 381, Guangzhou 510641, People's Republic of China.
Zhenda
Z
Tan
School of Chemistry & Chemical Engineering, South China University of Technology , Wushan Road - 381, Guangzhou 510641, People's Republic of China.
Huanfeng
H
Jiang
School of Chemistry & Chemical Engineering, South China University of Technology , Wushan Road - 381, Guangzhou 510641, People's Republic of China.
Min
M
Zhang