883192-17-4Relevant academic research and scientific papers
Exploring the reactivity towards acidic protic ligands of the Di-μ-hydroxo complex [NBu4]2[Pd2{C 4(COOMe)4}2(μ-OH)2]: A convenient precursor in the preparation of new palladacyclopentadiene complexes
Sanchez, Gregorio,Vives, Jorge,Lopez, Gregorio,Serrano, Jose Luis,Garcia, Luis,Perez, Jose
, p. 2360 - 2367 (2005)
The dinuclear hydroxo complex [NBu4]2[Pd 2{C4(COOMe)4}2-(H-OH)2] (I) reacts in a 1:2 molar ratio with a wide variety of protic electrophiles H(L) bearing different sets of donor atoms (L = O∧O, N∧S or O∧N) to give the mononuclear anionic palladium(n) derivatives with the general formula [Pd{C4(COOMe)4}(L)]- [O∧O = salycilaldehydate (sal) (1), acetohydroxamate (ahx) (2) and benzohydroxamate (bhx) (3); N∧S = 2-pyridinthiolate (spy) (4), 2-pyrimidinthiolate (spym) (5), 3-methyl-2-imidazolin-thiolate (meimt) (6) and 2-aminothiophenolate (2-atp) (7); O∧N = N-phenylsalycilaldiminate (N-phsal) (8), N-p- chlorophenylsalycilaldiminate (N-clsal) (9), N-p-tolylsalycilaldiminate (N-tolsal) (10), 2-aminophenolate (2-atp) (11), 2-pyrrole-carboxaldeydate (2-pcal) (12), 8-hydroxiquinolinate (oxin) (13), picolinate (2-pic) (14)]. Structural characterisation by X-ray diffraction of complexes 5, 8 and 13 confirmed the proposed formula. Dinuclear complexes [NBu4] 2 [Pd{C4(COOMe)4}(μ-az)]2 (az = pyrazolate (pz) (15), triazolate (tz) (16) and 3,5-dimethylpyrazolate (3,5-Me2pz) (17) were obtained when treating I with azoles in the same molar ratio, and also treating the hydroxo complex with chloranilic acid (chl) (18) and squarate (sq) (19) in 1:1 proportion to yield compounds [NBu 4]2[Pd{C4(COOMe)4} 2{(μ-O-O)}] with the ligands acting as bis-bidentate ones. A related process takes place when (I) reacts with ammonium O,Oprime;- dialkyldithiophosphates in acetone under mild conditions and complexes [NBu 4][Pd{C4(COOMe)4}{S(S)P(OR)2}] (R = Me (20), Et (21), iPr (22)) are obtained. Deprotonation of secondary amines Et2NH, Pr2NH, piperidine or morpholine by (I) in the presence of carbon disulfide leads to the corresponding dithiocarbamate complexes [Pd{C4(COOMe)4}-(S2CNR2)] 23-26. (I) also promotes the nucleophilic addition of water to pyridine-2-carbonitrile and a mononuclear complex 27 containing the pyridine-2-carboxamidate ligand is formed. Its structure has been determined by a single-crystal diffraction study. The new complexes were fully characterised by analytical and spectroscopic techniques (FAB-MS, IR; 1H, 13C and 31P-NMR). Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
