| abstract |
The invention provides a novel synthetic method for the preparation of an alkyne-1 compound of the general formula R(CH 2 ) n C≡CH, in which R is a monovalent hydrocarbon group and n is an integer of 4, 5 or 6, which compound is useful as an intermediate of various organic compounds or, in particular, of several sexual pheromone compounds of noxious insects expected to give a promising means for the extermination of the insects. The method comprises reacting an ω-bromo-1-alkyne compound of the formula Br(CH 2 ) n C≡CH, e.g. 8-bromo-l-octyne, with a Grignard reagent of the formula RMgX, e.g. cis-3-octenylmagnesium chloride, in tetrahydrofuran, preferably, in the presence of a catalyst which is dilithium copper tetrachloride or lithium copper dichloride. |