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Rate and equilibrium constants for methyl pyruvate oxime formation were determined as a function of pH over the range 0-7 in aqueous solution at 30°C and ionic strength 0.5 by spectrophotometric methods. The reaction occurs with rate-determining carbinolamine dehydration over the entire range of pH investigated. Carbinolamine dehydration is not susceptible to detectable general acid-base catalysis by a carboxylic acid buffer or hydroxylamine/hydroxylammonium ion buffer. Specific acid catalysis for carbinolamine formation is dominant at pH values below 5. Above that value, a pH-independent, water-catalyzed reaction becomes apparent. The pH-independent carbinolamine dehydration is unusually important with this substrate. Copyright

Ruthenium-catalyzed heteroannulation between enamides and isocyanates has been realized as a complementary approach to conventional strategies for the synthesis of pyrimidin-4-ones. High step-A nd atom-economy was achieved for the rapid construction of such privileged scaffolds, which are found in a multitude of pharmaceutical compounds. The generality and practicability of this transformation were reflected by the broad scope of substrates with diverse functional groups, large-scale synthesis, and late-stage diversification.

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A wide variety of oximes were prepared from different types of alcohols with hydroxylamine hydrochloride using 1-methylimidaziloum nitrate, [Hmim][NO3], ionic liquid as a reaction medium and promoter under microwave irradiation. This protocol provides a one-pot oxime synthesis with high yields that is facile, eco-friendly and the ionic liquid can be recovered and reused.

A catalytic hydrovinylation of N-acetylenamines with ethylene is reported. This new hydrovinylation reaction is catalyzed by a ruthenium hydride complex, RuHCl(CO)(PCy3)2, providing a series of N-acetylamines with a quaternary carbon center with up to 99% yield.

(Chemical Equation Presented) A variety of oximes were synthesized from the corresponding alcohols, alkyl halides, or alkyl sulfonates without using external oxidants. With this simple two-step procedure involving substitution with readily available TsNHOTBS and subsequent treatment with CsF, a range of oximes were prepared including the ones hardly preparable with conventional procedures.

An α-oxime ester derivative prepared via treatment of an acetylenedicarboxylate or an α-keto ester with hydroxylamine underwent C-alkylation to the C=N bond of the oxime group by a Lewis-acid-promoted reaction with a trialkylzincate or a dialkylzinc reagent. The O-N bond of the thus obtained adduct was reductively cleaved under hydrogenolysis in the presence of the Pd-C catalyst to afford an α-amino ester. Treatment of the oxime derivative prepared from methyl 5-bromo-2-oxopentanoate with the trialkylzincate gave an α-alkyl proline derivative via the addition reaction followed by the intramolecular attack upon a bromine-bearing carbon. The reaction of ethyl 4-oxo-2-pentynoate with hydroxylamine formed an isoxazole derivative by way of the intramolecular attack of an in situ-generated oxime to the carbonyl group. From this isoxazole derivative, ethyl 2-amino-4-oxo-2- pentenoate was given by the Pd-C-catalyzed hydrogenolysis. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.

An indium mediated procedure has been developed for the allylation of activated O-functionalised oximes and nitriles as exemplified by a variety of glyoxylate derivatives. This method gives the corresponding free (or protected) amine in a one pot-process. The method is regiospecific and is carried out under remarkably mild conditions so that even oxime esters can be subjected to the typical reaction conditions.

Novel metal chelating compounds, and radiometal, e.g., technetium-99m complexes thereof. The compounds can be used to radiolabel small biologically active species with minimal effect on their biodistribution and activity. The compounds have formula (a) or (b): STR1 where Z is (CR2)n or (CR)n, n is 2 or 3, X is a ligand comprising S, N or O, each R is H or C1-C20 substituted or unsubstituted hydrocarbon group, provided that 1-3 CR2 groups represent a CO (amide) moiety, and provided that 1-3 R may each comprise a targeting group and/or a protein reactive functionality.

Bis(trimethylsilyl)formamide reacts with aldehydes in refluxing chloroform, or at room temperature with catalysis by trimethylsilyl trifluoromethanesulfonate, to give 1-acylamino-1-(trimethylsiloxy)alkanes; similar results are obtained with other bis(trimethylsilyl)amides, but surprisingly not with bis(trimethylsilyl)acetamide, and addition of bis(trimethylsilyl)formamide to ketones and acetals can also be accomplished using TMS triflate as catalyst.

Novel substituted phenylphosphinyloxy- and phenylphosphinylthio-iminocarboxylates, synthesis thereof, intermediates therefor, and the use of said novel compounds for the control of weeds.