31419-01-9Relevant academic research and scientific papers
Effect of Pressure on the 1,3-Dipolar Cycloaddition Reaction of Diphenyldiazomethane to Carbon-Carbon Multiple Bonds
Swieton, Gernot,Jouanne, Joern von,Kelm, Hartwig
, p. 1035 - 1040 (1983)
The volume profiles for the 1,3-dipolar cycloadditon reactions of diphenyldiazomethane to dimethyl acetylenedicarboxylate, diethyl maleate, diethyl fumarate, and maleic anhydride were measured in various solvents.Generally, the volumes of activation amoun
Regioselectivity of the thermal van Alphen–Hüttel rearrangement of 4- and 5-mono- and 4,5-disubstituted 3,3-diphenyl-3H-pyrazoles
Vasin,Razin,Bezrukova,Petrov
, p. 862 - 872 (2016/07/30)
Thermal van Alphen–Hüttel rearrangement of methyl 3,3-diphenyl-3H-pyrazole-4-carboxylate, 3,3-diphenyl-3H-pyrazole-4-carbonitrile, and methyl 5-methyl-3,3-diphenyl-3H-pyrazole-4-carboxylate involves completely regioselective migration of one phenyl group from the 3-position to N2with formation of aromatic 1H-pyrazole system. Thermal rearrangement of methyl 3,3-diphenyl-3H-pyrazole-5-carboxylate leads to the formation of methyl 4,5-diphenyl-1H-pyrazole-3-carboxylate as a result of migration of the 3-phenyl group exclusively to the C4atom and subsequent prototropic isomerization. Under analogous conditions, methyl 4-methyl-3,3-diphenyl-3H-pyrazole-5-carboxylate, methyl 5-(methanesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carboxylate, methyl 5-(benzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carboxylate, and dimethyl 3,3-diphenyl-3H-pyrazole-4,5-dicarboxylate have been regioselectively converted into the corresponding 4H-pyrazoles. Thermolysis of 5-(4-methylbenzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carbonitrile gives rise to a mixture of 1H- and 4H-pyrazoles, the former considerably prevailing, whereas the corresponding 1H-pyrazoles are formed as the only product from 5-(methanesulfonyl)- and 5-(benzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carbonitriles.
A Synthetic Route to Bicyclic Pyrazolenines via 3-Chloropyrazolines and the Ring Openning of Pyrazolenines to Diazolakenes
Nakano, Yoshihiko,Hamaguchi, Masashi,Nagai, Toshikazu
, p. 5912 - 5919 (2007/10/02)
Treatment of 5,5-disubstituted 3-chloro-1-pyrazolines, derived from the reaction between disubstituted diazomethanes and dimethyl chlorofumarate, with triethylamine gives the corresponding 3,3-disubstituted 3H-pyrazoles in good yield.This method was appli
