- Direct conversion of carboxylic acids to various nitrogen-containing compounds in the one-pot exploiting curtius rearrangement
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Herein we report, a single-pot multistep conversion of inactivated carboxylic acids to various N-containing compounds using a common synthetic methodology. The developed methodology rendered the use of carboxylic acids as a direct surrogate of primary amines, for the synthesis of primary ureas, secondary/tertiary ureas, O/S-carbamates, benzoyl ureas, amides, and N-formyls, exploiting the Curtius reaction. This approach has a potential to provide a diversified library of N-containing compounds, starting from a single carboxylic acid, based on the selection of the nucleophile.
- Kumar, Arun,Kumar, Naveen,Sharma, Ritika,Bhargava, Gaurav,Mahajan, Dinesh
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p. 11323 - 11334
(2019/09/10)
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- Identification and formation pathway of laccase-mediated oxidation products formed from hydroxyphenylureas
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Hydroxyphenylureas are the first main metabolites formed in the environment from pesticide and biocide urea compounds. Because fungi release potent exocellular oxidases, we studied the ability of laccases produced by the white rot fungus, T. versicolor, to catalyze in vitro the transformation of five hydroxyphenylureas, to identify transformation pathways and mechanisms. Our results establish that the pH of the reaction has a strong influence on both the kinetics of the reaction and the nature of the transformation products. Structural characterization by spectroscopic methods (NMR, mass spectrometry) of eleven transformation products shows that laccase oxidizes the substrates to quinones or to polyaromatic oligomers. Slightly acidic conditions favor the formation of quinones as final transformation products. In contrast, at pH 5-6, the quinones further react with the remaining substrate in solution to give hetero-oligomers via carbon-carbon or carbon-oxygen bond formation. A reaction pathway is proposed for each of the identified products. These results demonstrate that fungal laccases could assist the transformation of hydroxyphenylureas.
- Jolivalt,Neuville,Boyer,Kerhoas,Mougin
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p. 5046 - 5054
(2007/10/03)
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- 3,4,5-Trifluorobenzeneboronic acid: A mild and versatile catalyst for the one-pot synthesis of acyl azides from carboxylic acids
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Acyloxyboron intermediates generated from carboxylic acids and 3,4,5-trifluorobenzeneboronic acid react with sodium azide to furnish the corresponding acyl azides in moderate to good yields.
- Tale,Patil
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p. 9715 - 9716
(2007/10/03)
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- Synthesis of acyl azides from carboxylic acids using cyanuric chloride
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A mild, efficient and general method for the preparation of acyl azides from carboxylic acids and sodium azide using cyanuric chloride is described.
- Bandgar,Pandit
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p. 3413 - 3414
(2007/10/03)
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