One-pot borylation/arylation of 4-chloroquinolines and its application for the synthesis of various quinoline-based pharmacophores

Abstract

Herein, we describe a new protocol for one-pot borylation/arylation of 4-chloroqunolines. The reaction proceeds through a palladium catalyzed one-pot two step process. In the first step borylation of differently substituted 4-chloroquinolines take place with bis(pinacolato)diboron (B2pin2) or bis(neopentylglycolato)diboron (B2neo2) with Pd(PPh3)2Cl2 and KOAc and in the second step arylation with aryl halides in the presence of PPh3, K3PO4 and H2O furnish synthesis of C-4 arylated quinolines. This method gives access to various structurally interesting and pharmaceutically relevant C-4 arylated quinolines through CC bond formation under simple and efficient condition. Additionally, it offers a new synthetic protocol for future functionalization of quinolines at C-4 position which has been encountered in various quinoline based drugs and biologically important scaffolds.