Pyrazole 3-nitro-4-cyano

Perhaps the most useful of these 4,5-dihydro-I/7-pyrazole based routes, however, are those where the intermediate is simply oxidized with manganese(IV) oxide. As in the synthesis of 3,3-dimethyl-l-nitro-2-phenylcyclopropene (5), this sometimes makes possible the synthesis of precursors not available by the diazoalkane to acetylene addition route. In other cases, man-ganese(IV) oxide oxidation gives yields which are at least as good and often better than the diazoalkane to acetylene addition route and this method has been applied to the synthesis of nitro-, cyano-, carboxymethyl-, phenyl-, and alkyl-substituted systems. ... 

Cases are known where pyrazoles are formed from aliphatic diazo compounds and cyano-olefins,462,493 or nitro-olefins, the latter reaction being studied systematically by Parham and co-workers, who established that the relatively stable nitropyrazolines initially formed eliminate nitrous acid when heated with acid.484-486 (See also reference 486a.) When the diazo compound is gem-disubstituted, a pyrazole is formed by migration of one of the groups, which was... 

Some 5-nitro-2-thienyl-pyrazoles have been prepared for a study of their antimicrobial activity. The oximes of thienyl- and selenienyl-carboxamides, prepared from the nitriles and hydroxylamine, give 1,2,4-oxadiazoles by reaction with triethyl orthoformate in BFs etherate. Starting from cyano-thiophens and cyano-selenophens, thienyl- and selenienyl-triazoles and tetrazines were prepared. From the jS-diketone (184) the triheterocyclic (185) was obtained... 

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