1981 年 101 巻 2 号 p. 193-198
The 1, 3-cycloaddition of diazomethane to α-methylenephenylacetate, apoatropine, aposcopolamine and atropic acid methyl ester, was studied and 3-phenyl-3-alkoxycarbonyl-1-pyrazolines obtained. Alkamine esters of these compounds were rather stable, however, methyl ester of 1-pyrazoline derivative was changed to 1H-2-pyrazoline derivative and 3-phenylpyrazole under basic conditions. And also, methyl ester of 1-pyrazoline derivative was rearranged to 1H-2-pyrazoline derivative in acidic solutions. When chloroform solution of methyl ester of 1-pyrazoline derivative was kept standing at room temperature of heated at 50°, 1-phenyl-1-cyclopropanecarboxylic acid methyl ester was obtained.