Pyrazolo! 1,2-a pyrazole

Pyrazolo[3,4-c]pyrazole, tetrahydro-rearrangement, 5, 250 PyrazoIo[4,3-c]pyrazole, tetraaryl-electrophilic substitution, 6, 1035 oxidation, 6, 1034-1035 reduction, 6, 1035 vacuum pyrolysis, 6, 1035 Pyrazolo[ 1,2-a]pyrazole-l, 5-diones synthesis, 6, 991 Pyrazolo[ 1,2-a]pyrazoles reactions, 6, 1038 ring opening, 6, 983... 

Bromo-1 -methylbenzo[c]pyrazolo[ 1,2-a]pyrazole -3,9-dione 4-(p-Chlorobenzal)-l,3-diphenyI-2-pyrazolin-5-one... 

The pyrazolo[ 1,2-a ]pyrazole ring system is susceptible to thermolysis, photolysis, reduction and hydrogenolysis. Two successive electrocyclic ring opening processes are responsible for the formation of the heteropolyene (66) when (64) is heated the C-vinylazomethine imine (65) is proposed as the intermediate (75TL1125). 

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