112403-68-6Relevant articles and documents
Hindered ester formation by SN2 azidation of N-acetoxy-N-alkoxyamides and N-alkoxy-N-chloroamides-novel application of HERON rearrangements
Glover, Stephen A.,Mo, Guoning
, p. 1728 - 1739 (2007/10/03)
Treatment of N-acetoxy-N-alkoxyamides or N-alkoxy-N-chloroamides with sodium azide in aqueous acetonitrile results in SN2 displacement of chloride and the formation of reactive N-alkoxy-N-azidoamides. The reaction with N-acetoxy-N-benzyloxybenzamide has been studied kinetically (k294 = 2 L mol-1 s-1) and azidation of N-formyloxy-N-methoxyformamide has been modeled computationally at the pBP/DN*//HF/6-31G* level of theory. The anomeric amides N-alkoxy-N-azidoamides decompose intermolecularly and spontaneously to esters and two equivalents of nitrogen. This extremely exothermic process facilitates the formation, in excellent yields, of highly hindered esters.
Evidence for the Formation of Nitrenium Ions in the Acid-catalysed Solvolysis of Mutagenic N-Acetoxy-N-Alkoxybenzamides
Campbell, John J.,Glover, Stephen A.,Hammond, Gerard P.,Rowbottom, Colleen A.
, p. 2067 - 2080 (2007/10/02)
In aqueous acetonitrile, N-acetoxy-N-alkoxybenzamides undergo acid-catalysed solvolysis by the AAl1 mechanism to give acetic acid and nitrenium ions.This is indicated by an inverse dependence of the acid-independent rate constant, kH, upon the activity of water, a solvent kinetic isotope effect of 0.44 and positive Σ(excit.) values.In addition, relief of steric compression at the nitrogen enhances the rate of solvolysis.Hammett correlations with ?+ substituent constants were found for the rates of solvolysis of para-substituted-N-acetoxy-N-butoxybenzamides and N-acetoxy-N-(para-substituted benzyloxy) benzamides.This fact and the low ρ-values of -1.35 and -1.56, respectively, are indicative of a strong build-up of positive charge in the transition state which has both nitrenium ion and oxonium ion character and is in accordance with computed molecular-orbital properties of N-alkoxynitrenium ions.Greater levels of mutagenicity have been measured for those compounds which are more readily solvolysed to nitrenium ions.