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The aryl palladium complexes [PdI(C6H4CH2OH-2)(N∧N)] (N∧N = bpy = 2,2′-bipyridyl (1a), tbbpy = 4,4′-di-tert-butyl-2,2′-bipyridine (1b), tmeda = N,N,N′,N′-tetramethylethylenediamine (1c)) were synthesized by oxidative addition of 2-iodobenzyl alcohol to one equivalent of “[Pd(dba)2]” (dba = dibenzylideneacetone) in the presence of the N∧N ligands. By reaction of 1a with three equivalents of XyNC (Xy = 2,6-dimethylphenyl) the insertion complex trans-[PdI{C(═NXy)(C6H4CH2OH-2)}(CNXy)2] (2) was formed. The reaction of 1a with KOtBu resulted in the formation of the chelate complex [Pd(κ2-C,O-C6H4CH2O-2)(bpy)] (3), which crystallizes as pairs of molecules bridged by hydrogen bonds to water of crystallization. Complex 3 reacts with XyNC, forming the cyclic imidate N-(2,6-dimethylphenyl)-2-benzofuran-1(3H)-imine (4). By reaction of 3 with various primary alkyl halides RCH2X, the complexes [PdX(C6H4CH2OCH2R-2)(bpy)] (X = I, R = H (5a), X = Br, R = Ph (5b), p-C6H4CH2Br (5c), p-C6H4Br (5d), and p-C6H4I (5e)) were obt...

The dinuclear complexes [C6H2{PdBr(N∧N)}2-1,4-((E)-CH═CHPh)2-2,5] (N∧N = tbbpy = 4,4′-di-tert-butyl-2,2′-bipyridine (1a), tmeda = N,N,N′,N′-tetramethylethylenediamine (1b)) have been synthesized by oxidative addition of trans,trans-2,5-distyryl-2,4-dibromobenzene to 2 equiv of “[Pd(dba)2]” (dba = dibenzylideneacetone) in the presence of the N∧N ligands. A similar reaction with N∧N = bpy = 2,2′-bipyridine afforded the mononuclear complex [PdBr{C6H2(Br-4){((E)-CH═CHPh)2-2,5}(bpy)] (2). The reaction of 1a,b with PhC≡CPh, MeC≡CMe, and PhC≡CMe in the presence of TlOTf or AgClO4 gave the dipalladated indacenediide complexes [(μ-η,η-C12H2Bn2-1,5-R4-2,3,6,7){Pd(N∧N)}2](OTf)2 (Bn = benzyl, R = Ph, N∧N = tbbpy (3a), tmeda (3b); R = Me, N∧N = tbbpy (4a), tmeda (4b)) and [(μ-η,η-C12H2Bn2-1,5-Ph2-2,6-Me2-3,7){Pd(N∧N)}2](A)2 (N∧N = tbbpy, A = OTf (5a), ClO4 (5a′); N∧N = tmeda, A = OTf (5b)). The reactions of 2 with the same alkynes afforded the indenyl complexes [Pd(η-C9H2Bn-1-R2-2,3-((E)-CH═CHPh)-5-Br-6)(bpy)](A) (R =...

[2 + 3] Cycloaddition reactions of the di(azido)-PdII complex trans-[Pd(N3)2(PPh3)2] (1) with an organonitrile RCN (2), under heating for 12 h, give the bis(tetrazolato) complexes trans-[Pd(N4CR)2(PPh3)2] (3) [R = Me (3a), Ph (3b), 4-ClC6H4 (3c), 4-FC6H4 (3d), 2-NC5H4 (3e), 3-NC5H4 (3f), 4-NC5H4 (3g)]. The reaction of trans-[Pd(N3)2(PPh3)2] (1) with propionitrile (2h) also affords, apart from trans-[Pd(N4CEt)2(PPh3)2] (3h), the unexpected mixed cyano-tetrazolato complex trans-[Pd(CN)(N4CEt)(PPh3)2] (3h′) which is derived from the reaction of the bis(tetrazolato) 3h with propionitrile, with concomitant formation of 5-ethyl-1H-tetrazole, via a suggested unusual oxidative addition of the nitrile to PdII. The [2 + 3] cycloadditions of [Pd(N3)2(PTA)2] (4) (PTA = 1,3,5-triaza-7-phosphaadamantane) with RCN (2), under heating for 12 h, give the bis(tetrazolato) complexes trans-[Pd(N4CR)2(PTA)2] (5) [R = Ph (5a), 2-NC5H4 (5b), 3-NC5H4 (5c), 4-NC5H4 (5d)]. All these reactions are greatly accelerated by microwave irradiation (1 h, 125 °C, 300 W). Taking advantage of the hydro-solubility of PTA, a simple liberation of 5-phenyl-1H-tetrazole from the coordination sphere of trans-[Pd(N4CPh)2(PTA)2] (5a) was achieved. The complexes were characterized by IR, 1H, 13C{1H} and 31P{1H} NMR spectroscopies, ESI+-MS, elemental analyses and, for 3b, also by X-ray structure analysis. Weak agostic interactions between the CH groups of the triphenylphosphines and the palladium(II) centre were found.

The first palladium complex with an indacenediide ligand has been obtained by an unprecedented process involving the reaction of diphenylacetylene with a dipalladated 2,5-distyrylbenzene complex.