Abstract A kinetic study of the covalent hydration of a series of nitrobenzofuroxans, to give the corresponding hydroxy σ-adduct, in aqueous solution is reported. Analysis of the data obtained in the pH range 0.8–13 has allowed dissection of the observed rates into forward ( k 1 H 2 O , k 2 OH- ) and reverse ( k − 1 H + , k –2 ) rate constants as well as the obtention of pKa values for H 2 O addition
摘要 报道了一系列硝基苯并呋喃的共价水合反应动力学研究,得到相应的羟基 σ-加合物,在水溶液中。对在 pH 值范围 0.8-13 中获得的数据的分析允许将观察到的速率分解为正向 (k 1 H 2 O , k 2 OH- ) 和反向 ( k − 1 H + , k –2 ) 速率常数作为对碳环添加 H 2 O 的 pKa 值的获得。基于全局和局部 DFT 的反应性描述符用于合理化在反应速率常数中观察到的趋势并通过实验解释主要反应产物。反应性-选择性双重描述符已被用于表征可能驱动共价水合反应的区域选择性。
The Diels–Alder reactivity of nitrobenzofuroxans: mono- and di-adducts of isoprene and 2,3-dimethylbutadiene. New convenient precursors to naphtho- and phenanthreno-furoxanic and -furazanic structures
The reactions of a series of differently substituted nitrobenzofuroxans with isoprene and 2,3-dimethylbutadiene have been investigated. A variety of mono- and di-adducts resulting from normal electron demand Diels–Alder condensations involving the activated C6C7 and/or C4C5 double bonds of the carbocyclic ring as the dienophile contributors have been identified and structurally characterized. The regioselectivity
研究了一系列不同取代的硝基苯并呋喃与异戊二烯和2,3-二甲基丁二烯的反应。正常电子需求产生的各种单加合物和二加合物已被鉴定并在结构上表征了狄尔斯-阿尔德缩合反应,涉及碳环的活化的C 6 C 7和/或C 4 C 5双键作为亲二烯体的贡献者。发现反应的区域选择性强烈依赖于该环的取代模式。在4-硝基-6-X系列中,如果X是强吸电子取代基(X = NO 2,SO 2),则二烯分子首先加至C 6 C 7双键。CF 3),但如果X是中度活化的取代基(X = CN,CF 3),则连接到硝基活化的C 4 C 5双键上。随后发生第二分子二烯的添加,以在6-氰基,6-三氟甲基和6-硝基系统中产生高度立体选择性的二加合物。与此行为相反,在4-X-6-硝基系列(X = CN,CF 3)中仅获得了对应于二烯加至硝基活化的C 6 C 7双键的单加合物。4,6-二硝基四唑[1,5- a]吡啶与4,6-二硝基苯并呋喃的反
A novel reactivity pattern of nitro-benzofuroxans and -benzofurazans: the heterodienic behaviour of the five-membered ring
作者:R??gis Goumont、Muriel Sebban、Fran??ois Terrier
DOI:10.1039/b205164h
日期:2002.9.11
Evidence is presented that the N3C9C8N fragment of the annelated ring of some nitro-activated benzofuroxans and benzofurazans acts as a heterodiene contributor upon treatment with cyclohexadiene, thus highlighting a new facet of the reactivity of this class of heterocycles.
Potential antileukemic and immunosuppressive drugs. 3. Effects of homocyclic ring substitution on the in vitro drug activity of 4-nitrobenzo-2,1,3-oxadiazoles (4-nitrobenzofurazans) and their N-oxides (4-nitrobenzofuroxans)
作者:P. B. Ghosh、B. Ternai、M. W. Whitehouse
DOI:10.1021/jm00273a012
日期:1972.3
Straightforward one-pot synthesis of benzofuroxans from o-halonitrobenzenes in ionic liquids
作者:Aleksei B. Sheremetev、Nataliya S. Aleksandrova、Nikolai V. Ignat’ev、Michael Schulte
DOI:10.1016/j.mencom.2012.03.015
日期:2012.3
Treatment of o-halonitrobenzenes with sodium azide in a [empyrr][BF4]/Bu4NBr/H2O system gives benzofuroxans in high yields, with the recovery and reuse of the ionic liquid for at least ten times.