Synthesis of 5-(functionalized acyl)-1,3-dialkyl-substituted barbituric and 2-thiobarbituric acids

✍ Scribed by Hanafi H. Zoorob; Mohamed A. Ismail; Lucjan Strekowski

• Publisher: Journal of Heterocyclic Chemistry
• Year: 2001
• Tongue: English
• Weight: 53 KB
• Volume: 38
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.5570380207

✦ Synopsis

Abstract

A sodium derivative of 1,3‐dimefhylbarbituric acid or 1,3‐diethyl‐2‐thiobarbituric acid undergoes an efficient monoacylation at C5 by the reaction with ω‐chloroalkanoyl chloride or diacid dichloride in the presence of pyridine in tetrahydrofuran. A nucleophilic displacement of the chlorine in a 5‐chloroacetyl‐bartiburate can be accomplished by using a one‐pot procedure. By contrast, a similar transformation of a 5‐(chlorobutanoyl)barbituric acid requires intramolecular cyclization in the presence of a nonnucleophilic base followed by treatment with a nucleophile of the resultant 5‐[4,5‐dihydro(3__H__)‐2‐furylidene]barbiturate.