Iron(III) Chloride Hexahydrate as an Efficient Heterogeneous Recyclable Catalyst for the Synthesis of 2-Substituted Quinazolinones

The quinazolinone ring system as an important structural unit has been widely found in morethan 100 naturally occurring alkaloids and biological and pharmacological activities and extensiveapplications on pharmaceutical active molecules [1]. Its derivatives has never fadedsince the first report of 4(3H)-quinazolinone compound in 1869 [2].Quinazolinones are commonly prepared by the condensation of o-aminobenzamides with aldehydesusing oxidants or carboxylic acid derivatives under harsh conditions. Recently, oxidativecondensations of the alcohol, methylarene, or amines with o-aminobenzamides havealso been developed. In spide of these notable advances they generally suffer from one ormore drawbacks such as requirement of stoichiometric or excess amounts of strong oxidants,high temperatures, and transition metal catalysts [3, 4].Herein, we report that iron(III) chloride hexahydrate can be used as an effective catalyst forthe synthesis of quinazolinone derivatives by the condensation of o-aminobenzamides withaldehydes using with DDQ as an efficient and easily recyclable oxidant.