Cinnolines, tetrahydro-, from

Tetrahydro-[l,2,4]triazolo[4,3-h]cinnolines have been prepared from 3-hydrazino-5,6,7,8-tetrahydrocinnolines and the reagents just described for (17) (71BSF3043), and also by condensing 2-hydroxymethylenecyclohexanone with 4-amino-1,2,4-triazole (79JCS(P1)3085). 

R = H R = OMe) were obtained from the corresponding hydrazones in the former case the main product of the reaction was 1,2,3,4-tetrahydro-carbazol-l-one. Better yields were reported for the cyclization of 32 (R = Me R = H) and for the cyclohexane-1,2-dione mononaphthylhydra-zones, " the products from the last two being dehydrogenated to the fully aromatic naphtho[c] cinnolines. 

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