2443-30-3Relevant articles and documents
Bismuth chloride-sodium nitrite: A novel reagent for chemoselective N-nitrosation
Chaskar, Atul C.,Langi, Bhushan P.,Deorukhkar, Amol,Deokar, Hrushikesh
experimental part, p. 604 - 612 (2009/07/04)
Bismuth(III) chloride-sodium nitrite was used as a mild and efficient reagent for N-nitrosation of various tetrazoles, secondary amines, and amides under ambient conditions. Nitrosation took place chemoselectively at the nitrogen atom, giving corresponding N-nitroso derivatives in good to excellent yield. Copyright Taylor & Francis Group, LLC.
Reactivity of nitrogen nucleophiles towards S-nitrosopenicillamine
Munro, Andrew P.,Williams, D. Lyn H.
, p. 1989 - 1993 (2007/10/03)
We report the results of a kinetic study of the reactions of a number of nitrogen nucleophiles with the nitrosothiol S-nitrosopenicillamine (SPEN). The range of nucleophiles includes primary, secondary and tertiary aliphatic amines, together with hydrazine, hydroxylamine, azide ion, ammonia, semicarbazide, thiomorpholine and S-methylcysteine. Secondary amines form N-nitrosamines quantitatively. As expected, reaction occurs via the free base forms of the nucleophiles and consequently most of the reactions take place readily only at relatively high pH. Experiments were carried out with [nucleophile] ? [RSNO], and for many reactions, plots of the first order rate constant vs. [nucleophile] were linear. For ammonia and the primary amines, however, this plot tended to level off at high [nucleophile] and an explanation is offered involving the reversible formation of an inactive RSNO-amine complex, for which there is spectral evidence, in parallel with the main reaction. For the secondary amines there is a reasonably good Broensted plot with a β value of ～0.2. The much greater reactivities of S-methylcysteine and thiomorpholine, compared to those of primary amines and morpholine respectively are consistent with initial attack at the sulfur atom, followed by an internal rearrangement. Over the whole range of nucleophiles studied there is a reasonable correlation with the Ritchie N+ parameter, and not with the Pearson n scale. Comparisons are made with the corresponding reactions of alkyl nitrites and N-methyl-N-nitrosotoluene-p-sulfonamide (MNTS).
Reactivity of Nucleophilic Nitrogen Compounds towards the Nitroso Group
Garcia-Rio, Luis,Iglesias, Emilia,Leis, J. Ramon,Pena, M. Elena,Rios, Ana
, p. 29 - 37 (2007/10/02)
We discuss the reactivity of 43 nucleophilic nitrogen compounds towards the nitroso group of N-methyl-N-nitrosotoluene-p-sulfonamide (MNTS), and in some cases with alkyl nitrites.The series of nucleophiles considered is structurally very varied, includes members exhibiting the alpha effect, and covers 8 pKa units and a range of reactivities of almost five orders of magnitude.The values of solvent isotope effects and activation parameters have been measured and throw light on the structure of the transition states involved.Reactivities do not correlate well with thebasicity of the nucleophile, largely owing to the behaviour of primary amines, ammonia and nucleophiles with an alpha effect.Application of the curve crossing model suggests a relationship with vertical ionization potentials.The relationship with Ritchie's N+ scale is discussed, and interesting correlations with the reactivities of the same nucleophiles in various other chemical processes are noted.
