Verfahren zur Herstellung von vorwiegend alicyclischen Oligomeren von 1, 3-Dienen

摘要

Cyclic olefins are obtained by oligomerization of butadiene in the presence of a catalyst formed from nickel carbonyl and a polyolefinic or acetylenic compound while keeping the concentration of carbon monoxide low during the formation of the catalyst and during the reaction, e.g. of the order of 0.066% referred to the oligomerization mixture. The unsaturated component is preferably a hydrocarbon but may contain carboalkoxy or acyloxy groups; butadiene is particularly preferred. 1-400 mols of unsaturated compound is used per mol of nickel carbonyl and the catalyst may be formed in a hydrocarbon or ether solvent at 0-200 DEG C. and 1-25 atmospheres. Concentration of carbon monoxide is kept low by removal of gases continuously or at intervals or when the catalyst is formed in situ from nickel carbonyl and butadiene by having a low concentration of nickel carbonyl, e.g. below 0.1% by wt. of the butadiene. Otherwise the catalyst concentration may be 0.0005-5% and reaction is effected at 50-150 DEG C. In one embodiment the reaction is effected in stages adding further butadiene at each stage. Cyclooctadiene and cyclododecatriene are the principal products.