THE PREPARATION OF KETENE DITHIOACETALS AND THIOPHENES FROM CHLOROPYRIDINES CONTAINING AN ACTIVE METHYLENE GROUP

摘要

The base catalysed reaction of carbon disulphide with the active methylene groups of chloropyridines 4 and 7, followed by alkylation with reagents which also contain active methylene groups, lead to ketene dithioacetals. Further reaction with base afforded highly substituted thiophenes.