| 摘要 |
PURPOSE:To obtain the titled compound in high yield and quality from an inexpensive safe raw material, by reacting a malonic acid ester with a halogen compound in the presence of a phase-transfer catalyst and an alkali metal or alkaline earth metal oxide while removing water from the reaction system. CONSTITUTION:The objective compound of formula II (R5 is R4 when R1 is H and R5 is R1 when R1 is other than H) can be produced by reacting a malonic acid diester or malonic acid dinitrile of formula I (R1 is H, alkyl, alkenyl, alkynyl or aryl; R2 is alkyl; R3 is COOR2 or CN) with a compound of formula R4X (R4 is alkyl, alkynyl or aralkyl; X is halogen) in the presence of a phase transfer catalyst (e.g. quaternary ammonium salt) and an alkali metal or alkaline earth metal hydroxide or carbonate preferably at 40-110 deg.C while removing water from the system by refluxing dehydration or using a dehydration agent. |
