METHOD OF SYNTHESIS OF (Z)-1,2-ALKYL-1,2-DIETHYL-ETHYLENES Russian patent published in 2002 - IPC

FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to a method of synthesis of (Z)- 1,2-dialkylethylethylenes of the general formula (I) where R is n-C₃H₇, n-C₄H₉. The proposed method involves interaction of dialkyl-substituted acetylenes of the formula R-C≡C-R with triethylaluminium (Et₃Al) in the presence of zirconacene dichloride (Cp₂ZrCl₂) as a catalyst in their mole ratio = 10:(10-20):(0.1-0.5), respectively. Interaction is carried out under normal conditions in hexane medium at stirring for 8 h. Then to reaction mass at 0 C ethyltosylate (EtTs) is added taken in the mole ratio RC≡CR : EtTs = 10:(40-60) and reaction mass is stirred for 16-20 h at the room temperature followed by hydrolysis of reaction mass with hydrochloric acid solution. Indicated hydrocarbons can be used as monomers in processes of oligomerization, polymerization and as intermediate products in paint and varnish industry. EFFECT: enhanced of compounds of formula (I) from disubstituted acetylenes, high regio- and stereoselectivity. 1 tbl