Prepn. of 1-substd. imidazolidinone derivs. with higher yield and fewer steps

摘要

Prepn. of 1-substd. imidazolidinone derivs. of formula (I) and their salts comprises reducing a hydroxy amidino imidazolidinone of formula (II):R<1>- R<3> = H, opt. branched 1-6C alkyl, 2-4C alkenyl or Ph (opt. mono-or di-substd. by F, Cl, Br or I); or R<1>+R<2> = a 3-6C ring. Also claimed are methods of preparing (I) comprising: (A) reacting a nitrile of formula (III) with 1-5 equivs. of hydroxylamine or a hydroxylamine-protonic acid adduct to give (II) which is then reduced to (I); (B) reacting an isocyanate of formula (IV) with cyanamide to give (III) which is then treated with hydroxylamine and reduced to (I). Hal = F, Cl, Br or I; (C) cleaving a 1-haloazetidinone of formula (V) to give (IV) which is then treated with cyanamide and hydroxylamine and reduced to (I).