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The reaction of meta-phenylene-bis(1-methyl-1H-imidazole-2(3H)-selone) with [Pd2(μ-Cl)2(2-C6H4CH2NMe2)2] in dry benzene and glacial acetic acid resulted in the formation of an unsymmetrical 5,6-membered C,C,Se-Pd(II) pincer complex through C-H bond activation and extrusion of one selenium. This is the first example of a C,C,Se-Pd(II) complex wherein the central Pd(II) is simultaneously coordinated to a selone and an N-heterocyclic carbene. The chelated complex of the type [PdL2](2+)2[PF6](-) (L = bis(selone)) was isolated from the reaction of the bis(selone) with [PdCl2(PhCN)2] and NH4PF6. The unsymmetrical pincer complex was studied for Heck activity revealing its application as an acceptable catalyst in coupling of iodobenzene with acrylates and styrene.

The complexes [Pd(μ-ER)(η3-allyl)]2 (ER = EMes; E = S, Se; allyl = C3H5, C4H7) have been isolated by the reaction of [Pb(ER)2] n with [Pd2(μ-Cl)2(η3-allyl)2]. Similar reactions with [Pb(SeCH2CH2NMe2)2] n resulted in the formation of a trinuclear complex [Pd3Cl2(κ2-Se,N-SeCH2CH2NMe2)(η3-allyl)3]. Treatment of [Pd(μ-SR)(η3-C4H7)]2 with [Pd(SMes)2] n in 1:1 ratio yielded [Pd3(μ-SMes)4(η3-C4H7)2]. These complexes were characterized by elemental analyses and mass, UV−vis, and NMR spectroscopy. The structures of [Pd2(μ-EMes)2(η3-C4H7)2] (E = S, Se) were established by single-crystal X-ray diffraction analysis, which revealed a syn configuration. Two new structural motifs for [Pd3Cl2(κ2-Se,N-SeCH2CH2NMe2)(η3-C3H5)3] and [Pd3(μ-SMes)4(η3-C4H7)2] have also been identified. Pyrolysis of [Pd(μ-ER)(η3-C4H7)]2 yielded palladium chalcogenides, which were characterized by powder XRD and EDAX.

Thermolysis of [Pt 2 (µ-OR) 2 (C 8 H 12 OMe) 2 ] (R = Me or Ac) in hexadecylamine (HDA) at 210°C under argon atmosphere gave platinum nanoparticles which were characterized by XRD, EDAX and TEM analysis. Both spherical (~ 10 nm) and rod-like (~ 19 nm length with aspect ratio of 2⋅3) face centred cubic ( fcc) platinum metal nanoparticles could be isolated. The thermogravimetric analyses of these complexes revealed that they undergo a single step decomposition leading to the formation of platinum metal powder.