A Facile Microwave and SnCl2 Synthesis of 2,3-Dihydroquinazolin-4(1H)-ones
作者:Nicholas S. O'Brien、Adam McCluskey
DOI:10.1071/ch20101
日期:——
An elegantly simple, facile, and robust approach to a scaffold of biological importance, 2,3-dihydroquinazolin-4(1H)-ones, is reported. A catalytic 1 % SnCl2/microwave-mediated approach afforded access to pure material, collected by cooling and filtration after 20-min microwave irradiation at 120°C. A total of 41 analogues were prepared in isolated yields of 17–99 %. This process was highly tolerant
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
A one-pot synthesis of 2-aryl-2,3-dihydro-4(l<i>H</i>)-quinazolinones by use of samarium iodide
作者:Guoping Cai、Xiaoliang Xu、Zhifang Li、Ping Lu、William P. Weber
DOI:10.1002/jhet.5570390623
日期:2002.11
2-Aryl-2,3-dihydro-4(lH)-quinazolines have been prepared in a one-potsynthesis by samarium idoide (SmI2) promoted reaction of o-nitrobenzamide and aldehydes.
New conditions for synthesis of (±)-2-monosubstituted and (±)-2,2-disubstituted 2,3-dihydro-4(1H)-quinazolinones from 2-nitro- and 2-aminobenzamide
作者:Richard A. Bunce、Baskar Nammalwar
DOI:10.1002/jhet.672
日期:2011.9
An efficient synthesis of (±)‐2‐monosubstituted and (±)‐2,2‐disubstituted 2,3‐dihydro‐4(1H)‐quinazolinones has been developed using a dissolving metalreduction‐condensative cyclization strategy. Treatment of 2‐nitrobenzamide and an aldehyde or ketone with iron powder in refluxing acetic acid affords high yields of the title compounds. More complex ring systems are available by incorporating additional
Application of Organolithium in Organic Synthesis: A Simple and Convenient Procedure for the Synthesis of More Complex 6-Substituted 3 H -Quinazolin-4-ones
作者:Gamal A. El-Hiti
DOI:10.1007/s00706-003-0110-5
日期:2004.3.1
6-Methyl-3 H -quinazolin-4-one reacted with alkyllithium reagents at −78°C in THF to give 2-alkyl-1,2-dihydro-6-methyl-3 H -quinazolin-4-ones in high yields. However, no reaction took place when LDA was used as the lithium reagent. 6-Bromo-3 H -quinazolin-4-one reacted with excessive butyllithium to give 2-butyl-1,2-dihydro-3 H -quinazolin-4-ones in very good yields. However, the lithiation of 6-bromo-3