Reductions of Heterocycles Containing Three Nitrogen Atoms

Reduction of Heterocycles Containing Three Nitrogen Atoms 

The reduction of 1-hydroxymethyl- and 1-benzoyloxymethyl-benzotriazole (138) with lithium aluminum hydride and sodium borohydride has been investigated by Gaylord and Kay.148 The hydroxymethyl compound failed to undergo reduction with lithium aluminum hydride, apparently as a result of the immediate formation of an insoluble complex by reaction of the metal hydride with the 

The sodium borohydride reduction of benzotriazoles 138 and 139 gave, in good yield, benzotriazole 140. The cleavage of the carbon-nitrogen bond by the complex hydride thus occurred in preference to reduction of the ring or carbon-oxygen bond cleavage. 

Atkinson and Cossey148 reported that the reduction of 2-methyl-5,6-diphenyltriazinium iodide (141) with potassium borohydride in methanol led to a tetrahydro-2-methyl-5,6-diphenyl-l,2,4-triazine. The ultraviolet absorption spectrum of this tetrahydro-l,2,4-triazine showed a maximum at 297 mfi (loge = 4.06). A similar reduction of l-methyl-3,5,6-triphenyl-l,2,4-triazinium iodide (142) gave a dihydro-1,2,4-triazine, the ultraviolet spectrum of which had maxima at 273 mft (loge = 4.46) and 410-420 m/x (loge = 3.62). No assignment of 

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IX. Reduction of Heterocycles Containing Three Nitrogen Atoms 89... 

REDUCTION OF HETEROCYCLES CONTAINING THREE NITROGEN ATOMS... 

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