A novel protocol for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones from 2-aminobenzamides and aldehyde derivatives catalyzed by KOH/DMSO suspension has been developed. The present transition metal free methodology is operationally simple, scalable and varieties of 2,3-dihydroquinazolin-4(1H)-one derivatives were obtained in good to excellent yields in short reaction times.
Cyanuric Chloride Catalyzed Mild Protocol for Synthesis of Biologically Active Dihydro/Spiro Quinazolinones and Quinazolinone-glycoconjugates
作者:Moni Sharma、Shashi Pandey、Kuldeep Chauhan、Deepty Sharma、Brijesh Kumar、Prem M. S. Chauhan
DOI:10.1021/jo2020856
日期:2012.1.20
We have developed an efficient cyanuric chloride (2,4,6-trichloro-1,3,5-triazine, TCT) catalyzed approach for the synthesis of 2,3-dihydroquinazolin-4(1H)-one (3a–3x), 2-spiroquinazolinone (5, 7), and glycoconjugates of 2,3-dihydroquinazolin-4(1H)-one (10a, 10b) derivatives. The reaction allows rapid cyclization (8–20 min) with 10 mol % cyanuric chloride to give skeletal complexity in good to excellent
Expeditious synthesis of 2,3-dihydroquinazolin-4(1<i>H</i>)-ones in aqueous medium using thiamine hydrochloride (VB<sub>1</sub>) as a mild, efficient, and reusable organocatalyst
ABSTRACT A simple and straightforward synthesis of 2,3-dihydroquinazolin-4(1H)-ones is developed by reacting anthranilamide with various aldehydes or ketones under mild reaction conditions, using thiamine hydrochloride as a cost-effective, readily available, and green catalyst in water. Simple purification process, high yields within short reaction time, wide substrate scope, operational simplicity
Supported ceric ammonium nitrate: A highly efficient catalytic system for the synthesis of diversified 2,3-substituted 2,3-dihydroquinazolin-4(1H)-ones
作者:Someshwar D. Dindulkar、Jeongsu Oh、Veenita M. Arole、Yeon Tae Jeong
DOI:10.1016/j.crci.2013.11.008
日期:2014.10
Résumé A practically expeditious protocol has been developed for the cascade synthesis of 2,3-dihydroquinazolin-4(1H)-ones via the condensation of 2-aminobenzamide/2-aminobenzanilide and aromatic aldehydes using a catalytic amount of silica-supported ceric ammonium nitrate. This method affords rapid transformation at room temperature with good to excellent yields. Supplementary Materials: Supplementary material for this article is supplied as a separate file: mmc1.doc