The application of intramolecular coordination in the isolation of novel diaryl diselenides and their derivatives, monomeric chalcogenolato complexes of group 12 metals, glutathione peroxidase mimics, hybrid bi-, tri- and multidentate ligands and selenium-containing azamacrocycles is described.

Several new diaryl diselenides having intramolecular coordinating groups have been synthesized by ortho-lithiation/Na2Se2 routes in good yield. Bis[2-(N-phenylferrocenecarboxamide)] diselenide (10), bis[2-(N-tert-butylferrocenecarboxamide)] diselenide (11), (S)(S)-bis[2(-N-phenethylferrocene-carboxamide)] diselenide (12) were synthesized by the ortho-lithiation route. Bis[2-(N,N-dimethyl-aminomethylnaphthyl)] diselenide (13) was synthesized by lithium/bromide exchange reaction whereas bis(2,4-dinitrophenyl) diselenide (14) was prepared by the reaction of disodium diselenide with 2,4-dinitro-1-chlorobenzene. Thiol peroxidase-like activities of the diorganodiselenides have been evaluated by using H₂O₂ as substrate and PhSH as cosubstrate. Diselenides (13) and (14) with dimethylami-nomethyl- or nitro-donor groups in close proximity to selenium, show much better thiol peroxidase-like activities compared to diselenides10–12 with amide donor groups. Cyclic voltammetry study of diselenides10–12 derived from redox-active ferrocenamide has been carried out.

In this note we describe the synthesis of cadmium sulphide and selenide nanoparticles from the corresponding novel single source precursors, M[E(Ox)]₂ [E = S (1), Se (2); M = Cd; Ox = 2-(4,4-dimethyl-2-oxazolinyl)benzene] by thermolysing in tri-𝑛-octylphosphine oxide (TOPO) at 280°C, and their characterization by X-ray powder diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM) studies.

Recent trends in the area of intramolecularly coordinated organomercury and organochalcogens derivatives are reviewed. Intramolecular coordination in organomercury derivatives facilitates the formation of mercurametallamacrocycle and leads to novel metal-metal interaction with closed shell ions. It also plays a key role in stabilizing telluroxanes as well as in the activation of chalcogen-carbon bonds.

The synthesis and characterization of low-valent organoselenium and tellurium derivatives of hexabromododecahydrotriphenylene has been attempted. The reaction of hexabromododecahydrotriphenylene with in situ generated disodium dichalcogenides (Na₂E₂; E = Se, Te) afforded insoluble chalcododecahydrotriphenylene derivatives, 20, 21 respectively. Attempted aromatization of 20 and 21 using DDQ (2, 3-dichloro-5, 6-dicyano-1,4-benzoquinone) as an oxidizing agent afforded the co-crystals. The hexaselenophenyl derivative, 22 and the hexaselenocyanate derivative 23 were synthesized by the reaction of in situ generated sodium arylselenolate/potassium selenocyanate with hexabromododecahydrotriphenylene, respectively. The compounds were characterized by common spectroscopic tools and a few by single crystal x-ray crystallographic studies.