Preparation of a 3-thienylmalonic acid or a diester thereof comprising reacting in a polar solvent in the presence of a copper (I) halide a thiophene compound of formula: ##STR1## wherein X=I or Br, R.sub.1 =H or a C.sub.1-4 alkyl group, R.sub.2 =H or a C.sub.1-2 alkyl group and R.sub.3 =H or a C.sub.1-2 alkyl group, with the proviso that R.sub.2 and R.sub.3 cannot be an alkyl group simultaneously, with a mono-deprotonated methylene compound of formula: ##STR2## wherein a cation is present and Z'=Z" is CN or COOR in which R is a C.sub.1-4 alkyl group, or Z'=CN and Z"=COOR' in which R' is a C.sub.1-2 alkyl group, followed by hydrolysis by methods known per se to get the corresponding free acid.
制备
3-噻吩丙二酸或其二酯的方法包括在极性溶剂中,在
铜(I)卤化物的存在下,将式为:## STR1 ## 其中X = I或Br,R1 = H或C1-4烷基,R2 = H或C1-2烷基,R3 = H或C1-2烷基,但R2和R3不能同时为烷基的
噻吩化合物与式为:## STR2 ## 其中存在阳离子,Z' = Z"为CN或COOR,其中R为C1-4烷基,或Z' = CN且Z" = COOR',其中R'为C1-2烷基的单去质子亚甲基化合物反应,然后通过已知的
水解方法
水解得到相应的自由酸。