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A new cationic palladium complex [Pd(η5-C5H5)(PPh2Cy)2]BF4 (I) is prepared by the reaction of [Pd(acac)(PCyPh2)2]BF4 with cyclopentadiene in the presence of BF3·OEt2. The structure of complex I is determined by XRD. Results of the DFT studies at the BP86-D3/def2-TZVP level of theory along with QTAIM and NOCV methods suggest that the hapticity of the cyclopentadienyl ligand in I adopts an intermediate type of coordination between η3 and η5. Compound I demonstrates a catalytic activity in the reaction of 1,3-butadiene telomerization with methanol with a catalyst turnover number up to 43100 (mol·BD)/(mol·Pd) for 6 h and a 76% selectivity to telomeres. [ABSTRACT FROM AUTHOR]

The structure of complex [Pd(acac){P(NEt2)3}2]BF4 (I) is determined by XRD. In the crystal structure of I, the coordination sphere of palladium is characterized by a significantly distorted planar-square geometry of the central atom. Steric hindrance of the P(NEt2)3 ligand is determined using the XRD and DFT data (the Tolman cone angle is 170-175°). It is established that the pair of P(NEt2)3 ligands in the coordination sphere of palladium is represented by two isomers differing by the geometries (planar and pyramidal) of the nitrogen atom environment. DFT calculations at the BP86/def2-TZVP level of theory suggest that the difference between the substituent geometries in the ligands is due to steric hindrances. In combination with BF3·OEt2, compound I demonstrates catalytic activity in the addition polymerization of norbornene whose average activity reaches 3.6·105 g(NB)/(mol(Pd)·h) at 100 °C. [ABSTRACT FROM AUTHOR]

Reaction of Pd(acac)2 with BF3·OEt2 in the presence of tri(2-furyl)phosphine in toluene yields complex [Pd(acac)(TFP)2]BF4 (I) (TFP is tri(2-furyl)phosphine) whose structure is determined by XRD. The crystal structure of I contains short H⋯F contacts. The energies of these contacts are studied using DFT quantum chemical methods. Coordination complex I in combination with BF3·OEt2 in appropriate concentrations and solvents demonstrates catalytic activity in the reaction of morpholine allylic alkylation characterized by the catalyst turnover number from 198 mol to 268 mol of 4-allylmorpholine per mole of palladium and an integral selectivity to the main product of 88-99%. [ABSTRACT FROM AUTHOR]

A letter to the editor concerning the products of the norbornene additive polymerization applied as coatings in electronic engineering is presented.

A letter to the editor is presented in response to the article "Selective Dimerization of Styrene in the Presence of Catalysts of the Type [(Acac)Pd(PR3)2]BF4 + nBF3 . OEt2," by V. S. Tkach and colleagues in the 2007 issue.

A letter to the editor is presented in response to the article "Selective Dimerization of Styrene in the Presence of Catalysts of the Type [(Acac)Pd(PR3)2]BF4 + nBF3 . OEt2," by V. S. Tkach and colleagues in the 2007 issue.

Pd2(CHCC6H5)2(C5H7O2)3(BF3)2BF4 and Pd(acac)2 + 2PhA + 4BF3OEt2 are active catalysts for the polymerization of norbornene. For the Pd2(CHCC6H5)2(C5H7O2)3(BF3)2BF4 a “particular” catalyst activity up to 17,600 kg polynorbornene per mol Pd for an hour and viscosity average molar masses up to 520,000 g/mol were observed. IR and NMR spectroscopy study of the polymer showed the microstructure presented by the rr and mr triads with low diisotacticity. [Copyright &y& Elsevier]