Polyunsatd alkynes prepn from mono-substd acetylenes - and haloalkenes or haloalkynes, with cuprous salts and diazabicycloalkanes

摘要

Polyunsatd. alkynes of formula R1 - C is approx. = C - R2 (where R1 is H, opt. substd. alkyl, opt. substd. (poly)alkenyl, opt. substd. (poly)alkynyl; R2 is opt. substd. (poly)alkenyl, opt. subt. (poly)alkynyl) are prepd. by reacting a cpd. of formula R1.C is approx. = CH with a cpd. of formula X-R2 (where X is halogen) in the presence of a mixt. of a cuprous halide or cuprous cyanide, a bicyclic amidine base and =1 antioxidants, opt. in the presence of water, in org. solvent(s) at -40 degrees to +100 degrees C. Process gives high yields of sterically homogeneous forms of the prods., used as inters. for insect attractants. Reduced risk of fire and explosion makes process more suitable for indl. scale.