The imidazolium salt 3-methyl-1-(naphthalen-2-yl)-1H-imidazolium iodide (2) has been treated with silver(I) oxide and [{Pt(μ-Cl)(η(3)-2-Me-C3H4)}2] (η(3)-2-Me-C3H4 = η(3)-2-methylallyl) to give the intermediate N-heterocyclic carbene complex [PtCl(η(3)-2-Me-C3H4)(HCC*-κC*)] (3) (HCC*-κC* = 3-methyl-1-(naphthalen-2-yl)-1H-imidazol-2-ylidene). Compound 3 undergoes regiospecific cyclometallation at the naphthyl ring of the NHC ligand to give the five-membered platinacycle compound [{Pt(μ-Cl)(CC*)}2] (4). Chlorine abstraction from 4 with β-diketonate Tl derivatives rendered the corresponding neutral compounds [Pt(CC*)(L-O,O')] {L = acac (HL = acetylacetone) 5, phacac (HL = 1,3-diphenyl-1,3-propanedione) 6, hfacac (HL = hexafluoroacetylacetone) 7}. All of the compounds (3-7) were fully characterized by standard spectroscopic and analytical methods. X-ray diffraction studies were performed on 5-7, revealing short Pt-Pt and π-π interactions in the solid-state structure. The influence of the R-substituents of the β-diketonate ligand on the photophysical properties and the use of the most efficient emitter, 5, as phosphor converter has also been studied.

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Major Medicinal Plants of India is an important, highly useful, and recommended compendium of data on the chemical constituents, biological activity, and folk and traditional medicinal uses of approximately 145 species. The plants are arranged alphabetically by genus and species (not by family), and each plant is accompanied by a list of literature references (preponderantly on chemical composition), as well as a good

The phenyl propynoates (III), prepared from the phenols (I), are rearranged photochemically to give the hydroxyaryl ketones (IV).