Complexes of binucleating ligands. 20. Complexes of a new, easily accessible binucleating ligand containing an aliphatic thiolate bridging center

Coordination chemistry of dinucleating P2N2S ligands: preparation and characterization of cationic palladium complexes

The thioethers (4-tert-butyl-2,6-bis((2-(diphenylphosphino)ethylimino)methyl)phenyl)(tert-butyl)sulfane (tBuL3) and (4-tert-butyl-2,6-bis((2-(diphenylphosphino)ethylamino)methyl)phenyl)(tert-butyl)sulfane (tBuL4) react readily with [Pd(NCMe)2Cl2] to give the dinuclear palladium thiophenolate complexes [(L3)Pd2(Cl)2]+ and [(L4)Pd2(micro-Cl)]2+ (HL3=2,6-bis((2-(diphenylphosphino)ethylimino)methyl)-4-tert-butylbenzenethiol, HL4=2,6-bis((2-(diphenylphosphino)ethylamino)methyl)-4-tert-butylbenzenethiol). The chlorides in could be replaced by neutral (MeCN) and anionic ligands (NCS-, N3-, I-, CN-) to give the dinuclear PdII complexes [(L3)Pd2(NCMe)2]3+, [(L3)Pd2(SCN)2]+, [(L3)Pd2(N3)2]+, [(L3)Pd2(I)2]+, and [(L3)Pd2(CN)2]+. The acetonitrile ligands in are readily hydrated to give the corresponding amidato complex [(L3)Pd2(NHCOMe)]2+. All complexes were isolated as perchlorate salts and studied by infrared, 1H, and 31P NMR spectroscopy. In addition, complexes [ClO4].EtOH, [ClO4]2, [ClO4], [ClO4].EtOH, and [ClO4]2.MeCN.MeOH have been characterized by X-ray crystallography. The dipalladium complex was found to catalyse the vinyl-addition polymerization of norbornene in the presence of MAO (methylalumoxane) and B(C6F5)3/AlEt3.

Preparation and characterization of dinuclear Pd(ii) complexes of binucleating tetraaza-thiophenolate ligands

The thioethers 4-tert-butyl-2,6-bis((2-(dimethylamino)ethylimino)methyl)phenyl(tert-butyl)sulfane (tBu-L3) and 4-tert-butyl-2,6-bis((2-(dimethylamino)ethylimino)methyl)phenyl(tert-butyl)sulfane (tBu-L4) react with PdCl2(NCMe)2 to give the dinuclear palladium thiophenolate complexes [(L3)Pd2Cl2]+ (2) and [(L4Pd2(mu-Cl)]2+ (3) (HL3= 2,6-bis((2-(dimethylamino)ethylimino)methyl)-4-tert-butylbenzenethiol, HL4 = 2,6-bis((2-(dimethylamino)ethylamino)methyl)-4-tert-butylbenzenethiol). The chloride ligands in could be replaced by neutral (NCMe) and anionic ligands (NCS-, N3-, CN-, OAc-) to give the diamagnetic Pd(II) complexes [(L3)Pd2(NCMe)2]3+ (4), [(L3)Pd2(NCS)2]+ (5), [(L3)Pd2(N3)2]+ (6), [{(L3)Pd2(mu-CN)}2]4+ (7) and [(L3)Pd2(OAc)]2+ (9). The nitrile ligands in and in [(L3)Pd2(NCCH2Cl)2]3+ are readily hydrated to give the corresponding amidato complexes [(L3)Pd2(CH3CONH)]2+ (8) and [(L3)Pd2(CH2ClCONH)]2+ (10). The reaction of [(L3)Pd2(NCMe)2]3+ with NaBPh4 gave the diphenyl complex [(L3)Pd2(Ph)2]+ (11). All complexes were either isolated as perchlorate or tetraphenylborate salts and studied by IR, 1H and 13C NMR spectroscopy. In addition, complexes 2[ClO4], 3[ClO4]2, 5[BPh4], 6[BPh4], 7[ClO4]4, 9[ClO4]2, 10[ClO4]2 and 11[BPh4] have been characterized by X-ray crystallography.

Tsalen- and Tsalpn-Based Nickel Complexes with Two Aldehyde Functionalities as Potential Synthons for Thiophenolate-Containing Di- and Polynucleating Acyclic and Macrocyclic Ligands

Tsalen- and tsalpn-based nickel complexes with aldehyde functionalities have been prepared (tsalen = N,N'-ethylenebis(thiosalicylideneaminato)(2-) and tsalpn = N,N'-propane-1,3-diyl(thiosalicylideneaminato)(2-)). One of the complexes has been structurally characterized: Ni(pftp) (pftp = N,N-ethylene(6-formyl-4-methyl-2-methyliminatothiophenolato)(2-)) crystallizes in the monoclinic space group C2/c with a = 28.761(7), b = 8.582(2), c = 7.841(4) Å; beta = 98.92(3) degrees, and Z = 4. Ni(pftp) and Ni(eftp) (efpt = N,N-ethylene(6-formyl-4-methyl-2-methyliminatothiophenolato)(2-)) were used as synthons for acyclic and macrocyclic complexes and a prototype of each has been structurally characterized. The Schiff base derivative of Ni(pftp) and 2-(2-aminoethyl)pyridine gives the acyclic complex, Ni(peptp) (peptp =N,N-propane-1,3-diyl(6-(N-(2-ethylpyridyl)iminomethyl)-4-methyl-2-methyliminatothiophenolato)(-)) with the two ethylpyridyl arms furnishing an "open site", which in this complex is vacant, and a "closed site", in which the Ni(2+) is located. Ni(peptp) crystallizes in the monoclinic space group P2(1)/n with a = 10.247(7), b = 21.886(8), c = 15.662(9) Å; beta = 92.58(6) degrees, and Z = 4. Schiff base condensation of Ni(pftp) with diaminopropane gave two different macrocyclic dinickel complexes [L(1)Ni(2)](ClO(4))(2) and L(2)Ni(2). L(1) and L(2) are the 2 + 2 and 4 + 4 macrocycles, respectively, comprising two propylenediamine and two thiocresol units and four propylenediamine and four thiocresol units, respectively. Crystals of L(2)Ni(2) (L(2) = (10,23,36,49-tetramethyl-13,26,39,52-tetramercapto-2,6,15,19,28,32,41,45-octaaza-1,7,14,20,27,33,40,46-octaene[7.7.7.7]metacyclophane) are of poor quality and crystallize in the C2/c space group with a = 31.517(14), b =8.980(2), c = 26.822(12) Å; beta = 117.17(2) degrees, and Z = 4.