Dehydration of LnCl3·6H2O (Ln=Tb, Nd, Dy) in the reaction with i-Bu3Al, Et3Al, Et2AlCl, EtAlCl2 and formation of the complexes LnCl3·3(BuO)3PO

The dehydration of toluene insoluble salts TbCl3·6H2O (1), DyCl3·6H2O (2) and NdCl3·6H2O (3) in their reaction with organoaluminum compounds (RnAlX3−n): i-Bu3Al, Et3Al, Et2AlCl, EtAlCl2 and the influence of (BuO)3PO (TBP) on the process were studied. In the reaction of RnAlX3−n with the water of crystallization of salts 1–3, aluminoxanes and the following gases are formed: i-BuH for i-Bu3Al, EtH for Et3Al, EtH and HCl for Et2AlCl and EtAlCl2 as a result of the attack on the AlC or AlCl bond independent of the presence of TBP. In the absence of TBP the salts 1–3 are dehydrated by RnAlX3−n to give insoluble products LnCl3·0.5H2O·0.5(R2Al)2O, where R is alkyl for i-Bu3Al and Et3Al, or R is alkyl and Cl for Et2AlCl. The reaction of RnAlX3−n with 1–3 in the mixture of toluene–TBP at the ratio TBP/Ln≥12:1 results in the complete removal of water from LnCl3·6H2O and leads to the formation of homogeneous solutions, containing aluminoxanes and LnCl3·3TBP complexes. Homogeneous solutions, obtained after interaction in the system NdCl3·6H2O+TBP+PhMe+R3Al were then activated with either i-Bu3Al or (i-Bu2Al)2O and used as catalysts for polymerization of butadiene. All the catalysts were highly active for polymerization of butadiene, and produced a low-molecular polybutadiene.