83702-47-0Relevant academic research and scientific papers
Ring Transformation of 6H-Cyclopropapyrazolopyrimidine. IV (1). Reduction and Reaction of 5a-Acetyl-6a-ethoxycarbonyl-5a,6a-dihydro-6H-cyclopropapyrazolopyrimidine-3-carbonitriles with Primary Amines
Kurihara, Takushi,Nasu, Keiko,Tani, Tsutomu
, p. 519 - 523 (2007/10/02)
The reaction of 5a-acetyl-6-ethoxycarbonyl-5a,6a-dihydro-6H-cyclopropapyrazolopyrimidine-3-carbonitrile (1a) with benzylamine gave ethyl 1-benzyl-5-cyano-8a,9-dihydro-2-methyl-1H-pyrrolo-pyrazolopyrimidine-8a-carboxylate (2a), in addition to 5-acetyl-3-benzylamino-1-(4-cyanopyrazol-3-yl)-2-pyridone (3).Reaction of 1a with aniline gave ethyl 6-acetyl-8-anilino-3-cyano-7,8-dihydro-4H-pyrazolodiazepine-8-carboxylate (4), in addition to etzhyl 3-cyano-7-methyl-6-pyrazolopyrimidineacrylate (5).On the other hand, the same reactions of 1b with benzylamine or aniline gave 2b or 8b,respectively.Though catalytic hydrogenation of 1a over 5percent palladium-carbon proceeded by ring fission of cyclopropane ring to give 9, 1a (or 1b) afforded 4,5-dihydro derivatives (13 or 15) by catalytic hydrogenation over platinum oxide. The reactivity of 5-methoxy-4,5,5a,6a-tetrahydro-6H-cyclopropapyrazolopyrimidine (16), which arerelated analogs of 1a,b, is also described.
