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The Pd(II) complexes [Pd(Cp)(L)n]m[BF4]m were synthesized via the reaction of cationic acetylacetonate complexes with cyclopentadiene in the presence of BF3∙OEt2 (n = 2, m = 1: L = PPh3 (1), P(p-Tol)3, tris(ortho-methoxyphenyl)phosphine (TOMPP), tri-2-furylphosphine, tri-2-thienylphosphine; n = 1, m = 1: L = dppf, dppp (2), dppb (3), 1,5-bis(diphenylphosphino)pentane; n = 1, m = 2 or 3: 1,6-bis(diphenylphosphino)hexane). Complexes 1–3 were characterized using X-ray diffractometry. The inspection of the crystal structures of the complexes enabled the recognition of (Cp–)⋯(Ph-group) and (Cp–)⋯(CH2-group) interactions, which are of C–H...π nature. The presence of these interactions was confirmed theoretically via DFT calculations using QTAIM analysis. The intermolecular interactions in the X-ray structures are non-covalent in origin with an estimated energy of 0.3–1.6 kcal/mol. The cationic palladium catalyst precursors with monophosphines were found to be active catalysts for the telomerization of 1,3-butadiene with methanol (TON up to 2.4∙104 mol 1,3-butadiene per mol Pd with chemoselectivity of 82%). Complex [Pd(Cp)(TOMPP)2]BF4 was found to be an efficient catalyst for the polymerization of phenylacetylene (PA) (catalyst activities up to 8.9 × 103 gPA·(molPd·h)−1 were observed) [ABSTRACT FROM AUTHOR]

Abstract: A series of novel [Pd(acac-O,O′)(PˆP)]BF4 and known complexes [Pd(acac-O,O′)(PR3)2]BF4 (PˆP = dppm (1), dppp (2), dppb (3), dppf (4); R = Ph (5), p-Tol (6), i-Pr (7); acac = 2,4-pentanedionato) were prepared by the reaction of [Pd(acac-O,O′)(MeCN)2]BF4 (1) with appropriate ligands. Complex 2 was characterized by single-crystal X-ray analysis. Models of the structure and IR wavenumbers assignments of the cations of 1–4 were obtained by DFT calculations. Synthesized complexes were tested as catalysts in the telomerization of isoprene and butadiene with diethylamine. In the case of telomerization of butadiene with diethylamine high catalyst activity (e.g. TOFav = 1940 h−1 and TON up to 17,480 for complex 5) was obtained. [Copyright &y& Elsevier]