Reaction of ketenes with N,N ‐Disubstituted 2‐Aminomethylenecyclo‐alkanones VI. Synthesis of N,N ‐Disubstituted 4‐Amino‐3,4‐dihydro‐3,3‐dithioethyl‐5,6‐polyrnethylene‐α‐pyrones

The reaction of dithioethylketene, a new dithioalkylketene prepared in situ from dithio‐ethylacetyl chloride and triethylamine, with N,N ‐disubstituted 2‐aminomethylenecycloalkanones gave the 1,4‐cycloadducts, namely N,N ‐disubstituted 4‐amino‐3,4‐dihydro‐3,3‐dithioethyl‐5,6‐polymethylene‐α‐pyrones.