Novel 5-halogeno-6-amino-nicotinic acid halides of the formula ##STR1## in which R represents hydrogen or alkyl, R.sup.1 represents hydrogen, alkyl or acyl or R and R.sup.1, together with the nitrogen atom to which they are bonded, represent an optionally substituted heterocyclic radical, R.sup.2 represents halogen and Hal represents halogen, are prepared by halogenating the corresponding nicotinic acids. The Co Hal moiety is converted to CH.sub.3 by reaction with R.sup.3 OMgCR.sup.4 (COOR.sup.3).sub.2 (IV) in which R.sup.3 represents C.sub.1-3 alkyl and R.sup.4 represents hydrogen or C.sub.1 -C.sub.2 -alkyl, and then hydrolyzing and decarboxylating the product.
式为 ##STR1## 的新型5-卤代-
6-氨基烟酸卤化物,其中R代表氢或烷基,R.sup.1代表氢、烷基或酰基或R和R.sup.1与它们结合的氮原子一起代表可选择取代的杂环基,R.sup.2代表卤素,Hal代表卤素,通过卤代相应的
烟酸制备。Co Hal基团通过与R.sup.3 OMgCR.sup.4(COOR.sup.3).sub.2(IV)反应转化为CH.sub.3,其中R.sup.3代表C.sub.1-3烷基,R.sup.4代表氢或C.sub.1-C.sub.2-烷基,然后
水解和脱羧产物。