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Changes in the luminescence characteristics of Tb3+ and Ce3+ lanthanide ions in the interaction of LnCl3 · 3(BuO)3PO complexes with iso-Bu3Al in the absence and presence of piperylene were studied. As a result, a new luminescence approach was proposed to study reaction mechanisms in the synthesis of lanthanide catalysts for diene polymerization.

The dehydration of toluene insoluble salts TbCl 3 ·6H 2 O ( 1 ), DyCl 3 ·6H 2 O ( 2 ) and NdCl 3 ·6H 2 O ( 3 ) in their reaction with organoaluminum compounds (R n AlX 3− n ): i -Bu 3 Al, Et 3 Al, Et 2 AlCl, EtAlCl 2 and the influence of (BuO) 3 PO (TBP) on the process were studied. In the reaction of R n AlX 3− n with the water of crystallization of salts 1 – 3 , aluminoxanes and the following gases are formed: i -BuH for i -Bu 3 Al, EtH for Et 3 Al, EtH and HCl for Et 2 AlCl and EtAlCl 2 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 R n AlX 3− n to give insoluble products LnCl 3 ·0.5H 2 O·0.5(R 2 Al) 2 O, where R is alkyl for i -Bu 3 Al and Et 3 Al, or R is alkyl and Cl for Et 2 AlCl. The reaction of R n AlX 3− 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 LnCl 3 ·6H 2 O and leads to the formation of homogeneous solutions, containing aluminoxanes and LnCl 3 ·3TBP complexes. Homogeneous solutions, obtained after interaction in the system NdCl 3 ·6H 2 O+TBP+PhMe+R 3 Al were then activated with either i -Bu 3 Al or ( i -Bu 2 Al) 2 O and used as catalysts for polymerization of butadiene. All the catalysts were highly active for polymerization of butadiene, and produced a low-molecular polybutadiene.

Triboluminescence of Ln(acac)3·H2O (Ln = Tb, Eu, Pr, Ce, Gd) was found. The UV radiation was detected for the first time as narrow bands caused by the emission of the adsorbed N2* molecules (transitions 3∏u → 3∏g) in the study of triboluminescence of lanthanide compounds. The emission of Ln3+* (ionic triboluminescence) was observed only for Tb3+* (λmax/nm: 490 (5D4-7F6), 545 (5D4-7F5), 580 (5D4-7F4)) and Eu3+* (λ?max/nm: 613, 614 (5D2-7F3)). The generation of N2* occurs due to the energy of electric fields appeared upon the destruction of crystalline samples of Ln(acac)3·H2O. The Tb3+* and Eu3+* ions are formed due to the energy transfer from the triplet level of the ligand (acacT1), which is excited by the light emitted from the N2* molecule.