Reaction of 4-substituted thiosemicarbazides with (2,4,7-trinitro-9H-fluoren-9-ylidene)propanedinitrile

4-Substituted thiosemicarbazides 4a-c reacted with (2,4,7-trinitro-9H-fluoren-9-ylidene)-propanedinitrile (2) in pyridine with admission of air to form spiro[fluorene-9,3'-(1,2,4-triazole)]derivatives 5a-c and (4-substituted thiosemicarbazono)propanedinitriles 6a-c in modest yields. 2,4,7-Trinitro-9-fluorenone (8) as well as one reduction product thereof and of 2, namely compounds 9 and 10, respectively are also found. A rationale for the conversions observed is presented.