Keto-enol tautomerization vs 1,2-hydrogen migration in acetyl chlorides

초록

To study the reaction mechanism of disubstituted acetyl chlorides (R=Me, Ph) keto-enol tautomerizations of neutral and cationic intermediate were studied in the presence of catalytic water molecules (see eq.1,2) using the ab initio MO method. Another possible mechanism which involves 1,2-hydrogen migration of cationic intermediate (eq.3) was also studied. These hydrogen migrations require considerable activation energies in the absence of water molecules. But the activation energies decrease as more catalytic water molecules introduced in the reaction system.