7,10A‐Methanocycloocta[ c,d ]indazoles: Diisophoranes incorporating the pyrazole ring system

Compounds of the novel 7,10a‐methanocycloocta[ c,d ]indazole ring‐system 5, 7 are obtained by the action of hydrazines on 1‐chloro(or hydroxy)diisophor‐2,7‐en‐3‐ones 1–3 . Their formulation agrees with their origin and their chemical and spectral characteristics. Analogous syntheses of two comparable ring‐systems include the production of a substituted 7,10a‐methanocycloocta[ g,h ][2,1]benzisoxazole 10 by a facile cyclodehydration of the oxime of diisophorone 9a , and that of the indole‐analogue 13 by the action of aniline on diisophorone‐1‐carboxylic acid 11 .