31419-02-0Relevant articles and documents
Rearrangements of 3H-Pyrazoles—Adducts of Dimethyl Acetylenedicarboxylate with Diphenyldiazomethane and 9-Diazofluorene
Vasin,Razin,Bezrukova,Popkova, Yu. A.,Somov
, p. 892 - 900 (2018)
Structurally related 3H-pyrazoles resulting from 1,3-dipolar cycloaddition of diphenyldiazomethane and 9-diazofluorene to dimethyl acetylenedicarboxylate undergo van Alphen–Hüttel rearrangement on heating in a polar solvent (methanol, ethanol, acetic acid