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The chelate complex [Pd(κ(2)-C,O-C6H4CH2O-2)(bpy)] () reacts with acetonitrile, cyanamides, or carbodiimides, in the presence of AgOTf (1 : 5 : 1 molar ratio) and residual water, to form complexes [Pd{κ(2)-C,N-C6H4{CH2OC([double bond, length as m-dash]NX)Y}-2}(bpy)](OTf), where X = H, Y = Me (), NMe2 (), NEt2 (), X = R, Y = NHR (R = (i)Pr (), Tol ()), as a result of the insertion of the unsaturated reagent into the O-Pd bond of and the protonation of one of the N atoms. In the absence of AgOTf the reaction of with TolN[double bond, length as m-dash]C[double bond, length as m-dash]NTol (Tol = p-Tolyl) results in the formation of the neutral complex [Pd{κ(2)-C,N-C6H4{CH2OC([double bond, length as m-dash]NTol)NTol}-2}(bpy)] (). Complexes and can be interconverted by deprotonation ( + KO(t)Bu) or protonation ( + KOTf + HOTf) reactions. When the reaction of with TolN[double bond, length as m-dash]C[double bond, length as m-dash]NTol in the presence of AgOTf is carried out in a 1 : 1 : 1 stoichiometric ratio, or for a short period of time, a mixture of and a mixed heterometallic Ag2Pd complex is obtained ( = [Ag(N-)2](OTf)). Complex is the major product when the AgOTf is added before the carbodiimide, and the reaction is stopped immediately. can also be obtained by reaction of with 0.5 equiv. of AgOTf. When complex [PdI(C6H4CH2OH-2)(bpy)] () reacts with (i)PrN[double bond, length as m-dash]C[double bond, length as m-dash]N(i)Pr in the presence of TlOTf, instead of AgOTf, a ca. 1 : 1 mixture of and [Pd{κ(2)-O,N-OCH2{C6H4{C([double bond, length as m-dash]NH(i)Pr)N(i)Pr}-2}}(bpy)](OTf) () forms. Complex is the result of the insertion of the carbodiimide into the C-Pd bond. Complexes have been extensively characterized by NMR spectroscopy, and the crystal structures of , , and ·2.5CHCl3·0.5Et2O have been determined by X-ray diffraction studies.

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...

[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.