<i>o</i>-Iodoxy Benzoic Acid–Mediated Synthesis of 3,5-Diarylisoxazoles and Isoxazole-3-carboxylic Acids

<div><p></p><p>A new, convenient, ecofriendly synthesis of 3,5-diarylisoxazoles is reported from α,β-unsaturated ketoximes. Similarly, a novel synthesis of isoxazole carboxylic acids is also reported. Both the methods use efficient, environmentally friendly, and nontoxic iodoxybenzoic acid (IBX) as an oxidative cyclizing reagent. Easy procedure, environmentally benign reaction conditions, and nontoxicity are advantages to the methodology.</p> </div

Synthesis and Reactivity of Platinum(II) <i>cis</i>-Dialkyl, <i>cis</i>-Alkyl Chloro, and <i>cis-</i>Alkyl Hydrido Bis‑<i>N</i>‑heterocyclic Carbene Chelate Complexes

Platinum­(II) <i>cis-</i>dimethyl and <i>cis-</i>dineopentyl complexes bearing the alkyl-substituted bis-NHC ligands L^{<i>t</i>‑Bu}, L^Me, and L^{<i>i</i>‑Pr} (L^{<i>t</i>‑Bu} = 1,1′-di-<i>tert</i>-butyl-3,3′-methylenedi­imid­azolin-2,2′-diylidene, L^Me = 1,1′-dimethyl-3,3′-methylenedi­imid­azolin-2,2′-diylidene, L^{<i>i</i>‑Pr} = 1,1′-diisopropyl-3,3′-methylenedi­imid­azolin-2,2′-diylidene) as well as novel <i>cis-</i>alkyl chloro and <i>cis-</i>alkyl hydrido compounds were synthesized. The reactivity of the dimethyl complexes toward dichloromethane and methanol was investigated. Reductive elimination of alkanes from <i>cis-</i>alkyl hydrido complexes requires much higher temperatures than in related bisphosphine systems, which limits their applicability for the generation of reactive, bent platinum(0) d¹⁰-ML₂ fragments for bond-activation chemistry. The platinum­(II) complexes were characterized by NMR and IR spectroscopy, mass spectrometry, elemental analysis, and X-ray diffraction in most cases