Replacement of Halogeno Substituents by Hydrazino, Azido, and Amido Groups

Replacement of Halogeno Substituents by Hydrazino, Azido, and Amido Groups 

Preparations of the corresponding hydrazino compounds from 2-chloro-3(or 6)-methylpyrazine and 2-chloro-3,6-dimethylpyrazine with 98% hydrazine in absolute ethanol at reflux (775) and from 2-chloro-3,5-dimethyl-, 2-chloro-3,5,6-trimethyl-, 2-chloro-5- and 6-methyl-3-propyl-, or 2-chloro-5,6-dimethyl-3-propylpyrazines with excess hydrazine hydrate in a sealed tube at 110-130° for 24 hours or for a similar period under reflux in butanol (826) have been described. 

3-Dichloropyrazine with hydrazine in ethanol gave 2-chloro-3-hydrazino-pyrazine (828, 919) and 2,6-dichloropyrazine with hydrazine hydrate in ethanol gave 2-chloro-6-hydrazinopyrazine (919, 973). 2,3,5-Trichloropyrazine with hydrazine gave 2,5-dichloro-3-hydrazinopyrazine (919). 

Tetrafluoropyrazine with ethanolic or methanolic hydrazine hydrate at 20° gave 

5- trifluoro-6-hydrazinopyrazine (851, 885) and in reactions with hydrazine, tetrachloropyrazine gave 2,3,5-trichloro-6-hydrazinopyrazine (888, 896), 2-chloro- 

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