Process for producing 1-octene from butadiene in the presence of titanium catalysts

A process in two steps for the preparation of 1-octene starting from butadiene which comprises:

• a first step (a) in which the bis-hydrodimerization of butadiene to 1,7-octadiene is effected in the presence of a catalyst based on palladium containing one or more tri-substituted monodentate phosphines, the molar ratio palladium/phosphines ranging from 50 to 3, in an aprotic polar solvent optionally containing an organic base;
• the above first step being carried out in the presence of a hydrogen donor;
• a second step (b) in which the partial catalytic hydrogenation of 1,7-octadiene, recovered at the end of the first step, to 1-octene, is effected;
• the above hydrogenation being carried out under hydrogen pressure or mixtures of hydrogen and nitrogen, in the presence of a catalyst;
• the above process being characterized in that in step (b) the catalyst is selected from titanium compounds in the presence of activators selected from one or more metal alkyls of group 13.