Four isomeric methylpseudoionones and two isomeric pseudoionones were separately synthesized by the Wittig reaction of citral a or citral b with the corresponding phosphonates. Two isomeric pseudoionones were also synthesized by the Wittig reaction of citral a or citral b with 2-oxopro-pylidenetriphenylphosphorane. The configurations and the conformations of the dienone systems in four methylpseudoionones and two pseudoionones were discussed on the basis of the infrared and ultraviolet absorption data.
柠檬醛 a 或
柠檬醛 b 与相应的
膦酸盐发生 Wittig 反应,分别合成了四种异构的甲基假阴离子和两种异构的假阴离子。
柠檬醛 a 或
柠檬醛 b 与 2-oxopro-pylidenetriphenylphosphorane 的 Wittig 反应也合成了两种异构体假
酮类化合物。根据红外线和紫外线吸收数据,讨论了四种甲基假ionone 和两种假ionone 中二烯酮系统的构型和构象。