7440-67-7 Catalytic performance of metal oxides for the synthesis of propylene carbonate from urea and 1,2-propanediol

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The influences of acid-base properties of metal oxides on the catalytic performance for synthesis of propylene carbonate from urea and 1,2-propanediol was investigated, and the reaction was stepwise. The amphoteric ZnO showed the best activity, and the yield of propylene carbonate reached 98.9%. The urea decomposition over oxides was characterized by using FTIR. ZnO, CaO, MgO and La2O3 were favorable to promote urea decomposition to form the isocyanate species, and the formation of isocyanate species was the key to urea alcoholysis. The catalytic activity of urea decomposition was consistency to the catalytic performance for synthesis of propylene carbonate. Based on these, the probable reaction mechanism was proposed. https://www.lookchem.com/CASDataBase_7440-67-7.htm

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100-64-1 On the Oxidation of Hydroxylamines with o -Iodoxybenzoic Acid (IBX)

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o -Iodoxybenzoic acid (IBX) is confirmed as a powerful tool for the oxidation of hydroxylamines. The synthetic route is demonstrated as efficient and user friendly, and is exploited on various carbohydrate-derived N,N-disubstituted hydroxylamines (cyclic, acyclic, and functionalized ones), affording the corresponding nitrones in good yields and regioselectivity. N-Monosubstituted hydroxylamines revealed an interesting divergent behavior depending on the reaction conditions. While IBX oxidation in dimethyl sulfoxide at 45 °C furnished oximes as reported, the oxidation in dichloromethane at room temperature afforded efficiently the unusual corresponding nitroso dimers. https://www.lookchem.com/CASDataBase_100-64-1.htm
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75-01-4 Nickel(I) Octaethylisobacteriochlorin Anion. An Exceptional Nucleophile. Reduction and Coupling of Alkyl Halides by Anionic and Radical Processes. A Model for Factor F-430

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100-40-3 ?-Arene Complexes of Nickel(II). Synthesis (from Metal Atoms) of (?-Arene)bis(pentafluorophenyl)nickel(II). Properties, ?-Arene Lability, and Chemistry

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