(1,3-butadiynyl)hydrazines: A new class of electron-rich alkadiynes

Article abstract of DOI:10.1055/s-1994-25482

3,4,4-Trichloro-1-trimethylhydrazino-3-buten-1-yne (3), obtained from perchlorobutenyne (1) and trimethylhydrazine (2) forms the novel (1,3-butadiynyl)hydrazines 6 by consecutive treatment with butyllithium and various electrophiles. On the other hand the 4-diethylamino-1-trimethylhydrazino-1,3-butadiyne (7) can be prepared by simultaneous treatment of 3 with butyllithium and lithium diethylamide. The 4-butyl and 4-phenyl substituted (1,3-butadiynyl)hydrazines 9 are obtained by the reaction of the corresponding 1,1-dichloro-1-buten-3-ynes 8 with two equivalents of lithium trimethylhydrazide. The reactivity of the new ynehydrazine derivatives 3, 6 and 9 toward electron-deficient olefins 11 and the α-pyrone 13 is examined.