A Simple Conversion of Creatinine to Creatol via Creatinine Chloroamine

Creatinine (2-amino-1,5-dihydro-l-methylimidazol-4-one) (1a) was converted in a simple way to creatol (2-amino-1,5-dihydro-5-hydroxy-l-methylimidazol-4-one) (1b) via creatinine chloramine (2-N-chloroamino-1,5-dihydro-l-methylimidazol-4-one) (3a), without using protecting groups. The creatinine chloroamine exists in the 2-N-chloroamino form (3a) in aqueous solution, but in the solid state, X-ray crystal analysis shows that it has the 2-N-chloroimino structure (2-N-chloroimino-1,5-dihydro-1-methylimidazol-4-one) (4a). Related imidazolones have also been prepared and are discussed.