A Facile synthesis of n,n′‐oligomethylenebis(4,5‐dihydrofuran‐3‐carboxamide)s using manganese(III)‐based radical cyclization of n,n′‐oligomethylenebis(3‐oxobutanamide)s with 1,1‐diarylethenes

The reaction of N,N′‐oligomethylenebis(3‐oxobutanamide)s with 1,1‐diarylethenes in the presence of manganese(III) acetate in acetic acid at 100° produced N N′‐oligomethylenebis(2‐methyl‐5,5‐diaryl‐4,5‐dihydrofuran‐3‐carboxamide)s. Similarly, the reaction of 3‐oxobutanamidoethyl 3‐oxobutanoate or N,N′‐(3,6‐dioxaoctamethylene)bis(3‐oxobutanamide) with 1,1‐diphenylethene gave (2‐methyl‐5,5‐diphenyl‐4,5‐dihydrofuran‐3‐amido)ethyl 2‐methyl‐5,5‐diphenyl‐4,5‐dihydrofuran‐3‐carboxylate or N,N′‐(3,6‐dioxa‐octamethylene)bis(2‐methyl‐5,5‐diphenyl‐4,5‐dihydrofuran‐3‐carboxamide) in moderate yields.