Copper‐Promoted Tandem Three‐Component Access to Quinazolin‐4(H)‐imines and Benzimidazo[1,2‐c]quinazolines

Abstract

A copper-catalyzed three-component assembly of cyanamides, 2-cyanoarylboronic acids and amines has been developed, providing functionalized quinazolin-4(H)-imines. Subsequent access to benzimidazo[1,2-c]quinazolines is achieved building again on copper-catalysis. One pot hydrolysis of quinazolin-4(H)-imines to quinazolin-4(3H)-ones is also described. Guanidine formation, cyclization and intramolecular CÀ H bond amination are key features of the process fully mediated by copper.

Metal-catalyzed reactions of organic nitriles and boronic acids to access diverse functionality

“…Organic & Biomolecular Chemistry and (66) followed by intramolecular cyclization of the resultant ketimine afforded isoquinoline (65) and isoquinolones (67), respectively. Arylboronic acids containing EDGs provided a higher yield than EWGs, suggesting electronic effects of the substituents.…”

Recent developments and perspectives in the copper-catalyzed multicomponent synthesis of heterocycles

“…A copper( ii )-based three-component reaction for the synthesis of quinazolin-4( H )-imines and benzimidazo[1,2- c ]quinazolines was reported by Neuville and team. 45 Quinazolin-4( H )-imines were successfully prepared from 2-cyanoarylboronic acids, cyanamides and amines in the presence of Cu(OAc) 2 and Na 2 CO 3 at 50 °C for 3 hours ( Scheme 36(a) ) and cyclization of newly formed NH-imine delivered benzimidazo[1,2- c ]quinazolines under oxidative copper catalysis ( Scheme 36(b) ). Under similar one pot hydrolytic conditions (more stronger conditions including Cu(OAc) 2 and Na 2 CO 3 , HCl, in THF/water (1 : 1) at a temperature of 70 °C for 12 h) quinazolin-4(3 H )-one was formed in 82% yield ( Scheme 36(c) ).…”

Microwave-Assisted Synthesis of Quinazolines and Quinazolinones: An Overview

“…Transition metal catalysis has also found extensive applications in the convenient and efficient synthesis of a wide variety of heterocyclic systems (Ma et al, 2017 ; Ramanathan and Liu, 2017 ; Tiwari and Bhanage, 2017 ; Chatterjee et al, 2018 ; Saikia et al, 2018 ; Chen et al, 2020 ; Debabrata et al, 2020 ; Ghosh et al, 2020 ; Janardhanan et al, 2020 ; Jiang et al, 2020 ; Kanwal et al, 2020 ; Kojima and Matsunaga, 2020 ; Li and Zhang, 2020 ; Nagata and Obora, 2020 ; Neto and Zeni, 2020a , b ; Pal et al, 2020 ; Ratmanova et al, 2020 ; Sahiba and Agarwal, 2020 ; Sonawane et al, 2020 ; Xuan et al, 2020 ). However, the literature survey revealed only an example of zinc (Shi et al, 2004 ), a limited number of iron-catalyzed (Melvin et al, 1992 ; Valderrama et al, 1999 ; Kanth et al, 2006 ; Yin et al, 2012 ; Gopalaiah et al, 2017 , 2019 ; Raut and Bhanage, 2017 ; Eidi et al, 2018 ), and relatively more copper-catalyzed reactions, leading to the synthesis of quinazoline and quinazolinone derivatives (Melvin et al, 1992 ; Chatterjee et al, 2018 ; Potuganti et al, 2018 ; Liang et al, 2019 ; Rodrigues et al, 2019 ; Donthiboina et al, 2020 ). The number of zinc, iron, and copper-catalyzed synthesis of quinazoline and quinazolinone derivatives were decreased when the literature survey was narrowed down to the choice of those reactions, performed specifically under MWI as an unconventional and environmentally benign source of energy, in accordance with the title of this review.…”