Methyldiacetylene, reaction with hydrazine hydrate

In the reaction of methyldiacetylene with hydrazine hydrate, both 3-ethylpyrazole (14) and 3,5-dimethylpyrazole (15) w e formed in a 4 1 ratio (73DIS). Both pyrazoles were preparatively isolated (3,5-dimethylpyrazole is crystalline and ethylpyrazole is a liquid) and identified by comparison with authentic samples. These data show that primary attack of monosubstituted 1,3-diynes by hydrazine is mainly directed toward the terminal acetylenic bond. 

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See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ , ]

See also in sourсe #XX -- [ , ]

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