Commercial Copper‐Catalyzed Aerobic Oxidative Synthesis of Quinazolinones from 2‐Aminobenzamide and Methanol

Abstract

The focus of this study was the development of a new synthetic method for quinazolinones based on the principles of Green Chemistry. Quinazolinones were synthesized from 2‐aminobenzamide using methanol as both the C1 source and a green solvent in the presence of base Cs2CO3. Additionally, a commercially available, economical copper complex was used as a catalyst in the reaction. The desired products were achieved in moderate to high yield with up to 99 % isolated yield.

Copper‐Catalyzed Oxidative C−C Cleavage of Carbohydrates: An Efficient Access to Quinazolinone Scaffolds

“…As expected, the desired product resulted in the insertion of 13 C as confirmed by 13 C‐NMR and mass spectroscopy (Scheme 6d). This result strongly suggests that our protocol can be widely used to synthesize a variety of quinazolinones in a cost‐effective way in comparison with the previously reported literatures, where they used C 1 source as a reagent and solvent [5a–c,e] . Next, the reaction was tested using glucose‐derived platform chemicals [7f,16a–c] like formic acid, glycolic acid and glycerol under the optimized reaction conditions replacing D ‐glucose (Scheme 6e).…”

“…In the year 2020, Kerdphon et al. reported a facile method for the synthesis of quinazolinones using methanol as both C 1 source and solvent using the same starting material (Scheme 1b) [5b] . Later in the same year, Anandhan et al.…”

Copper‐Catalyzed Acceptorless Dehydrogenative Coupling of 2‐Aminoaryl Methanols with Nitriles for Accessing Quinazolines and Quinolines

“…Due to the high medicinal value of quinazoline derivatives, development of new synthetic strategies still seems to be an attractive field of research. There are several synthetic approaches developed for the synthesis of quinazolines, [10a–f] among them one of the most recent methods is the acceptorless dehydrogenative coupling (ADC) of 2‐aminoaryl methanols with different nitriles. A significant development has been observed in the synthesis of quinazoline derivatives using this technique.…”

Tandem [3+1+1+1] Heterocyclization of α‐Acyl Ketene Dithioacetals with Ammonia and Methanol: Rapid Assembly of Polysubstituted Pyrimidines

“…Till date, much effort has been devoted to C‐methylation, [14b–e] C‐methoxylation, [14f–g] C‐hydroxymethylation, [14h–i] N‐methylation, [14j–k] N‐formylation, [14l–m] methoxycarbonylation [14n] . Recently, attention has turned to the construction of heterocycles with methanol as a C1‐source, including quinazolone, [15a–c] quinazoline [15d] and benzimidazole, [15] and remains an important field that urgently needs to be developed. To continue our research interest in exploring diverse reactivities of ketene dithioacetals, [16] which can act as a suitable substrate for the rapid assembly of complex pharmaceutical scaffolds, we herein propose an efficient [3+1+1+1] oxidative annulation avenue starting from simple α‐acyl ketene dithioacetals using prominent NH 4 OAc and methanol as appropriate nitrogen and C1 sources to give a diverse range of C6‐alkylthiopyrimidines derivatives.…”