ABSTRACT
This chapter describes the preparation of a large number of imidazolinone derivatives. The simplest syntheses of the imidazolinones start with an o-dicarboxylic acid or mixed anhydride. Of particular importance is the ability to produce these anhydrides in large quantities by a commercially acceptable process and at an economical price. A variant on the preceding route to the imidazolinones utilizes the a-aminocarboxylic acid amide rather than the nitrile. The initial condensation is carried out in methylene chloride, and the product is extracted into sodium hydroxide solution and then heated to effect cyclization to the imidazolinone. The arylimidazolinone can be prepared in an even simpler manner than that described for the o-dicarboxylic acid. It is well known that an activated methyl group can be converted by a Willgerodt reaction in a single reaction to a thioamide.
