Patent GB-872348-A (GB)
Title: A process for the production of oligomers of 1,3-dienes
Inventor: MUELLER HERBERT
IPC: C07C2/46
Filed: 1959-12-23
Abstract: Cyclic olefines and other liquid oligomers are obtained by contacting a 1,3-diolefine with a catalyst comprising (a) chromium (vi) oxide (b) an organic or inorganic acid halide or an organic acid anhydride or amide and (c) a trihydrocarbonyl aluminium or dihydrocarbonyl aluminium hydride.  Suitable molar ratios of the three constituents are (a):(b) between 1:3 and 3:1 and (a):(c) between 1:2 and 1:15, and a total amount of 0.5-10% by weight of diolefine is used.  Specified compounds (b) are acetyl chloride, propionyl chloride, butyric acid chloride, stearic acid chloride, benzoyl chloride, adipic acid chloride, phosphorus trichloride, phosphorus oxychloride, thionyl chloride, acetic anhydride, propionic anhydride, succinic anhydride, glutaric anhydride, N,N-dimethyl formamide, N,N-diethyl formamide, N,N-dibutyl formamide, N-formyl pyrrolidine, N,N-diethyl acetamide, N,N-dimethyl propionamide, N-methyl pyrrolidone and N-methyl caprolactam.  The compound (c) may be aluminium triphenyl, diethyl aluminium hydride, dipropyl aluminium hydride, di-iosbutyl aluminium hydride, aluminium triethyl, aluminium triisobutyl, aluminium tri-n-butyl and aluminium tripopyl.  The 1,3- diolefine may be 1,3-butadiene, which produces cyclooctadiene1,5, 1-vinylcyclohexene-3, cyclododecatriene1,5-9 (trans, trans, trans and trans, trans, cis) and higher unsaturated oligomers, isoprene, which produces isomeric trimethylcyclododecatrienes - 1,5,9,2,3- dimethylbutadiene - 1,3 which produces a trimer, probably 2,3,6,7,10, 11-hexamethyl-dodecatetraene-1,5,7,11, piperylene, which also p produces trimethylcyclododecatrienes-1,5,9, and cyclohexadiene-1,3, which produces a bicyclic dimer.  An inert solvent is preferably present which may be a hydrocarbon or chlorinated hydrocarbon and the reaction is effected at -50 to 150 DEG C. Increased pressure may be necessary to maintain the liquid phase.ALSO:A catalyst for polymerizing diolefines to cyclic olefines comprises (a) chromium (VI) oxide, (b) an organic or inorganic acid halide or an organic acid anhydride or amide (preferably substituted twice at the nitrogen atom and including lactams) and (c) a trihydrocarbonyl aluminium or dihydrocarbonyl aluminium hydride.  Suitable molar ratios of (a) to (b) are from 1:3 to 3:1 and of (a) to (c) from 1:2 to 1:15. Specified for (b) are acetyl chloride, propionyl chloride, butyric acid chloride, stearic acid chloride, benzoyl chloride, adipic acid chloride, phosphorus tri-chloride, phosphorus oxychloride, thionyl chloride, acetic anhydride, propionic anhydride, succinic anhydride, glutaric anhydride, N,N-dimethyl-, -diethyl-, or -dibutylformamide, N-formyl pyrrolidine, N,N-diethyl acetamide, N,N-dimethyl propionamide, N-methyl pyrrolidone and N-methyl caprolactam. Compound (c) may be aluminium triphenyl, diethyl-, dipropyl- or di-isobutylaluminium hydride, or aluminium-triethyl, -tri-isobutyl, -tri-n-butyl or -tripropyl.  The catalyst is preferably prepared by treating the chromium oxide with the acid derivative in the presence of an inert hydrocarbon or chlorinated hydrocarbon, e.g. in a ball mill, for 1-10 hours, and then adding the aluminium compound.