STUDIES ON NEW SYNTHETIC PATHWAYS TO DELTA ^ALPHA,BETA )-BUTENOLIDES FROM ALPHA -METHYLBUTANOLIDES. III: REGIOSPECIFIC PREPARATION OF ALPHA -METHYL-DELTA ^ALPHA,BETA )-BUTENOLIDES AND ALPHA -METHYLENE-GAMMA -BUTYROLACTONES BY ELECTROLYSIS OF ALPHA -CARBOXY-ALPHA -METHYLBUTANOLIDES AND BY OXIDATION OF ALPHA -DIMETHYLAMINO-ALPHA -METHYLBUTANOLIDES IN A FUSED LACTONE SYSTEMINAYAMA S; KAWAMATA T; SHIMIZU N et al.1980; CHEM. PHARM. BULL.; JPN; DA. 1980; VOL. 28; NO 1; PP. 282-287; BIBL. 7 REF.Article