Hindered ester formation by S<sub>N</sub>2 azidation of N-acetoxy-N-alkoxyamides and N-alkoxy-N-chloroamides—novel application of HERON rearrangements
作者:Stephen A. Glover、Guoning Mo
DOI:10.1039/b111250n
日期:——
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 molâ1 sâ1) 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 intramolecularly and spontaneously to esters and two equivalents of nitrogen. This extremely exothermic process facilitates the formation, in excellent yields, of highly hindered esters.
在水合乙腈中,N-乙酸氧基-N-烷氧基酰胺或N-烷氧基-N-氯酰胺与叠氮化钠反应会导致氯的SN2取代,并形成反应性N-烷氧基-N-叠氮酰胺。对N-乙酸氧基-N-苄氧基苯甲酰胺的反应动力学进行了研究(k294 = 2 L mol⁻¹ s⁻¹),并在pBP/DN*//HF/6-31G*理论水平上对N-甲酸氧基-N-甲氧基甲酰胺的叠氮化反应进行了计算模拟。异头酰胺N-烷氧基-N-叠氮酰胺会自发地发生分子内分解,生成酯和两分子氮气。这一极放热过程促进了高阻碍酯的高产率形成。
Campbell, John J.; Glover, Stephen A.; Hammond, Gerard P., Journal of the Chemical Society. Perkin transactions II, 1991, # 12, p. 2067 - 2080
作者:Campbell, John J.、Glover, Stephen A.、Hammond, Gerard P.、Rowbottom, Colleen A.
DOI:——
日期:——
A Comparison of the Reactivity and Mutagenicity of <i>N</i>-(Benzoyloxy)-<i>N</i>-(benzyloxy)benzamides
作者:Stephen A. Glover、Gerard P. Hammond、Antonio M. Bonin
DOI:10.1021/jo980863z
日期:1998.12.1
A new series of N-(acyloxy)-N-alkoxybenzamides, N-(benzoyloxy) -N-(benzyloxy)benzamides 7 have been synthesized and have been found to be direct acting mutagens in Salmonella TA100. They undergo A(Al)1 solvolysis to give N-benzoyl-N-(benzyloxy)nitrenium ions 3 under conditions of acid catalysis as well as unusual B(Al)2 reactions at nitrogen with hydroxide. The latter process affords as intermediates the anomeric hydroxamic esters 4 which rearrange intramolecularly to esters in a HERON reaction. Rates of acid-catalyzed solvolysis and reaction with hydroxide ions correlate with Hammett a values with low sensitivity (rho = +0.32 and +0.55, respectively) in accordance with the A(Al)1 and B(Al)2 mechanisms. Mutagenicity for the series also appears to correlate with Hammett sigma values but with low, negative sensitivity (rho = -0.57), and their biological activity may be attributable to their stability under conditions of the Ames assay and hydrophobic binding to DNA, rather than their chemical reactivity.
N-acetoxy-N-alkoxyamides - a new class of nitrenium ion precursors which are mutagenic
作者:Robert G. Gerdes、Stephen A. Glover、José F. ten Have、Colleen A. Rowbottom
DOI:10.1016/s0040-4039(00)99089-0
日期:1989.1
GERDES, ROBERT G.;GLOVER, STEPHEN A.;HAVE, JOSE F. TEN;ROWBOTTOM, COLLEEN+, TETRAHEDRON LETT., 30,(1989) N0, C. 2649-2652
作者:GERDES, ROBERT G.、GLOVER, STEPHEN A.、HAVE, JOSE F. TEN、ROWBOTTOM, COLLEEN+