| 摘要 |
Cyclododecatrienes, including the novel stereoisomer cis, cis, trans-1,5,9-cyclododecatriene, are obtained by trimerizing a conjugated diolefin in an organic solvent in the presence of a catalyst obtained from a chromium compound, particularly chromium acetylacetonate, and a compound of the formula RxAlXy in which R is a monovalent organic radical, X is a halogen, x=2.1-2.9 and y=0.9-0.1 such that x+y=3 which may be made by combining the requisite proportions of an organo aluminium compound and an organo aluminium halide or aluminium halide. The Al : Cr mol. ratio may be 4-30 : 1 and the ratio of gram mols. of diene to gram atoms of chromium may be 400-2,500 : 1. The preferred solvent is benzene, the diene concentration being 5-50% by weight. Reaction is effected at 0-100 DEG C. and up to 100 p.s.i.g. for up to 24 hours. The trimerizations of butadiene and isoprene are exemplified. Reference has been directed by the Comptroller to Specifications 848,951 and 849,236. |
