Acta Scientific Pharmaceutical Sciences (ASPS)(ISSN: 2581-5423)

Research Article Volume 7 Issue 3

Theoretical Investigation of Ag(I) Acid-catalysed Cascade Benz Annulation of N-(3-(2-(4-Methoxybenzoyl)phenyl)prop-2-yn-1-yl)benzamide for Synthesis of Naphthooxazole

Nan Lu*, Chengxia Miao and Xiaozheng Lan

College of Chemistry and Material Science, Shandong Agricultural University, Shandong Prov., P.R. China

*Corresponding Author: Nan Lu, College of Chemistry and Material Science, Shandong Agricultural University, Shandong Prov., P.R. China.

Received: January 25, 2023; Published: February 20, 2023


The mechanism is investigated for cascade benz annulation of N-(3-(2-(4-Methoxybenzoyl)phenyl)prop-2-yn-1-yl)benzamide catalyzed by Ag(I). The oxonium-ion generation and water nucleophilic addition induces ring opening hydroxylation, dual ketonization giving 1,5-diketone intermediate. Mediated by acid, the intramolecular cyclization, water elimination affords β-naphthol, from which the nucleophilic cyclization dehydration provides desired product naphthooxazole. The side reaction of acid-activated 5-exo-dig cyclization is accompanied by synergetic synchronous hydrolysis yielding indenone. The promotion of Ag(I) lies in the absolute energy and activation barrier decrease of oxonium-ion generation and water nucleophilic addition. The mediation of acid exists in intramolecular cyclization, nucleophilic cyclization dehydration and 5-exo-dig cyclization. The solvent influence of acid is smaller than Ag(I) from the reduction degree. These results are supported by Multiwfn analysis on FMO of specific TSs and MBO value of vital bonding, breaking.

Keywords: Oxazole-benzannulation; Naphtho[2,3‑d]oxazole; Oxonium-Ion; 5-exo-dig; Cyclization Dehydration


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Citation: Nan Lu., et al. “Theoretical Investigation of Ag(I) Acid-catalysed Cascade Benz Annulation of N-(3-(2-(4-Methoxybenzoyl)phenyl)prop-2-yn-1-yl)benzamide for Synthesis of Naphthooxazole". Acta Scientific Pharmaceutical Sciences 7.3 (2023): 11-23.


Copyright: © 2022 Nan Lu., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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