Process for preparation of ethene derivatives

摘要

The invention aims at providing a process by which ethene derivatives of enol form represented by the general formula (I) can be obtained in high yield with the configuration of enolic double bond being retained: (I) wherein E is C(=X)R4, S(O)nR4, P(=X)R4R5, or the like and which comprises reacting a compound represented by the general formula (II): (II) with a compound represented by the general formula (III): EY . . . (III) wherein E is as defined above; and Y is chloro, bromo, or CN in the presence of a base and a pyridine derivative represented by the general formula (IV): (IV) wherein R6 is alkyl or the like.