ADDITION OF ACETONE DIMETHYLHYDRAZONE TO DIMETHYL ACETYLENEDICARBOXYLATE

Acetone N,N-dimethylhydrazone and dimethyl acetylenedicarboxylate react at -30° to give 20% of the 1:2 adduct, 1-dimethylamino-2,2-dimethyl-3,4,5,6-tetracarbomethoxy-l,2-dihydropyridine, and 26% of a 1:1 adduct, dimethyl N-isopropylidine-N-dimethylamino-2-aminomaleate. At higher temperatures dimethyl 2-dimethyl-aminomaleate becomes an increasingly more important product. Dimethyloxalacetate dimethylhydrazone is a minor product at low temperatures. The 1:2 adduct gave upon photolysis the cis and trans forms of the aza-hexatriene, the former closing thermally at room temperature. © 1969, American Chemical Society. All rights reserved.