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。
Synthesis and thermal decomposition of N,N-dialkoxyamides
作者:Katherine M. Digianantonio、Stephen A. Glover、Jennifer P. Johns、Adam A. Rosser
DOI:10.1039/c1ob00008j
日期:——
esters using phenyliodine(III)bis(trifluoroacetate) (PIFA). Infrared carbonyl stretch frequencies and carbonyl 13C NMR properties have been reported, which support strong inhibition of amide resonance in these amides. Their thermal decomposition reactions in mesitylene at 155 °C proceed by homolysis to form alkoxyamidyl and alkoxyl free radicals in preference to HERON rearrangements to esters. The reactions
N,N-二烷氧基酰胺1c(实际上是尚未被研究的新型异头酰胺,即在氮原子上带有两个负电性酰胺的酰胺)的直接合成物,是使用苯基碘(III)双(三氟乙酸)酯(PIFA)由异羟肟酸酯直接以有用的产率合成的。据报道,红外羰基的拉伸频率和羰基的13 C NMR特性支持强烈抑制这些酰胺中的酰胺共振。它们的热分解反应均三甲苯在155℃下,通过均相分解形成烷氧基ami基和烷氧基自由基,而不是将HERON重排成酯。该反应遵循一级动力学,对于一系列N,N-二甲氧基-4-取代的苯甲酰胺,已确定了125-135 kJ mol -1的活化能以及弱的负熵活化。
Synthesis of isoquinolinone derivatives by Rh (III)-catalyzed C–H functionalization of <i>N</i>-ethoxybenzamides
Abstract An efficient Rh-(III)-catalyzed C-H functionalization of N-ethoxybenzamides with 1-alkynylcyclobutanols has been developed. Isoquinolone derivatives have been successfully synthesized through [4 + 2] annulation and ring opening reaction under mild conditions. The advantages of this efficient protocol include broad substrate scope and good to excellent yields. Graphical Abstract
Ruthenium-Catalyzed Redox-Neutral [4 + 1] Annulation of Benzamides and Propargyl Alcohols via C–H Bond Activation
作者:Xiaowei Wu、Bao Wang、Shengbin Zhou、Yu Zhou、Hong Liu
DOI:10.1021/acscatal.7b00031
日期:2017.4.7
transition-metal-catalyzed cycloaddition reactions, in which they generally serve as two-carbon reaction partners. Herein, we report ruthenium(II)-catalyzed redox-neutral [4 + 1] annulation of benzamides and propargyl alcohols, in which propargyl alcohols act as one-carbon units. This synthetic utility of propargyl alcohols led to a series of potentially bioactive N-substituted quaternary isoindolinones
HERON rearrangement of N,N?-diacyl-N,N?-dialkoxyhydrazines ? a theoretical and experimental study
作者:Stephen A. Glover、Guoning Mo、Arvi Rauk
DOI:10.1016/s0040-4020(98)01151-x
日期:1999.3
Ab initio calculations at the B3LYP/6-31G* level on N-methoxy-N-dimethylaminoformamide and its rearrangement to methyl formate and 1,1-dimethyldiazene through the HERON reaction, have been carried out in conjunction with an experimental study of the HERON reactions of N,N'-diacyl-N,N'-dialkoxyhydrazines. Substituent effects are in accord with the theoretical properties of the transition state and point to an anomerically driven process in which donor groups on the anomeric nitrogen and withdrawing groups on the migrating alkoxy oxygen facilitate the rearrangement process. (C) 1999 Elsevier Science Ltd. All rights reserved.