1,3-BUTADIYNES IN SYNTHESIS OF HETEROCYCLIC COMPOUNDS .I. 2,3-DIHYDRO-1,4-DIAZEPINE PYRAZOLE AND ISOXAZOLE DERIVATIVES

The condensation of 1,3-butadiyne with ethylenediamine has been shown to yield 5(7)-methyl-1H-2,3-dihydro 1,4-diazepine 2 ⇋ 3 rather than the reported 1,2,3,4-tetrahydro-1,4-diazocine (1). The reaction of hydrazine with appropriately substituted 1,3-butadiynes afforded pyrazoles 6a-d, while 1,4-diphenyl-1,3-butadiyne, when treated with hydroxylamine, yielded isoazole 7. Isomeric isoxazole 9 was also prepared and its structure was proven by nmr and mass spectrometric techniques. © 1969, American Chemical Society. All rights reserved.