Synthesis and structure of products of hydroxylamine acylation with 3-carboxy-2,2,5,5-tetramethylpyrrolinoxyl derivatives
摘要:
The reaction of NH2OH with the derivatives of 2,2,5,5-tetramethylpyrrolin-1-oxyl-3-carboxylic acid in all events led to the formation of a mixture of the corresponding nitroxylhydroxamic acid with a stable O-acylhydroxylamine. The ratio between the products depends on the nature of the acylating agent and under the Studied conditions varies from similar to 5.5 : 1 to 1 : 3 indicating the comparable nucleophilicity in this reaction of N and O atoms in the hydroxylamine. The most active chloride of the mentioned acid alongside the indicated products afforded in a considerable yield N,O-diacylhydroxylamine and the triacylated hydroxylamine, 3-{[(2,2,5,5-tetramethyl-1-oxylopyrrolin-3-yl)carbonyloxyimino][(2,2,5,5-tetramethyl-1-oxylopyrrolin-3-yl)carbonyloxy]methyl}-2,2,5,5-tetramethylpyrrolin-1-oxyl. The structure of both latter compounds was established by XRD analysis.
Synthesis and structure of 3-(hydroxycarbamoyl)-2,2,5,5-tetramethyl-2,5-dihydropyrrol-1-oxyl
摘要:
Hydroxyamination of 3-chlorocarbonyl-2,2,5,5-tetramethyl-2,5-dihydropyrrol-1-oxyl gave previously unknown 3-(hydroxycarbamoyl)-2,2,5,5-tetramethyl-2,5-dihydropyrrol-1-oxyl whose structure was determined by X-ray analysis. The hydroxamic acid fragment, has cis configuration, and the carbonyl group occupies distorted trans position with respect to the double bond in the planar dihydropyrrole ring.