Facile and One-Pot Synthesis of 2 H -Chromene Derivatives Mediated by Vinyl triphenylphosphonium Salt
作者:R. HekmatShoar、S. Souri、F. Faridbod
DOI:10.1080/10426500307876
日期:2003.7
An efficient process that converts 2-hydroxybenzaldehyde and their derivetives to chromene derivatives via intramolecular Wittig reaction is described.
描述了通过分子内 Wittig 反应将 2-羟基苯甲醛及其衍生物转化为色烯衍生物的有效过程。
CONVERSION OF IN SITU GENERATED STABILIZED PHOSPHORUS YLIDES TO CHROMENE DERIVATIVES IN SOLVENT-FREE CONDITIONS
intermediates, produced in the reactionbetweentriphenylphosphine and dialkyl acetylenedicarboxylates, by phenols (1-hydroxynaphthalene, 2-hydroxynaphthalene, 4-bromophenol, 2-hydroxybenzaldehyde, and 5-bromo-2-hydroxyben- zaldehyde) leads to vinyltriphenylphosphonium salts, which undergo electrophilic substitutionreaction with conjugate base to produce corresponding stabilized phosphorus ylides. Microwave was
Synthesis and characterization of dimethyl 6-bromo-2H-chromene-2,3-dicarboxylate: thermodynamic and kinetics investigations by computational and experimental studies
derivatives for use as drugs, including anticancer drugs, and for their biological activities. For this reason, the kinetics and synthesis of these compounds have attracted considerable attention, facilitating further developments and approaches for their synthesis. In this study, dimethyl 6-bromo-2H-chromene-2,3-dicarboxylate (4) was synthesized via the reaction between triphenylphosphine (1), dimethyl
现代社会依赖合成色烯衍生物用作药物(包括抗癌药)及其生物活性。由于这个原因,这些化合物的动力学和合成引起了相当大的关注,从而促进了其合成的进一步发展和方法。在这项研究中,通过三苯基膦(1),乙炔基二羧酸二甲酯(2)和5-溴-2-羟基苯甲醛酸(3)之间的反应合成了6-溴-2 H-色烯-2,3-二羧酸二甲酯(4)。在二氯甲烷存在下,然后使用IR,1 H,13 C和31进行表征1 H NMR。使用停止流和紫外可见分光光度法对反应的动力学和机理进行了理论和实验研究。反应机理涉及多个步骤,从反应物1和2之间快速反应生成I 1开始,并且使用停止流动装置研究了该步骤。使用紫外可见技术研究了中间体1(I 1)和3的消耗,发现它遵循一级动力学。确定化合物3的偏序为零,并且对反应速率没有影响。动力学数据表明该步骤提议的机制中的第4个是速率确定步骤。对不同温度下I 1消耗的研究允许使用两种线性化形式的Eyrin
Ramazani, Ali; Fattahi-Nujokamberi, Golam Reza, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2002, vol. 41, # 2, p. 407 - 408
作者:Ramazani, Ali、Fattahi-Nujokamberi, Golam Reza
DOI:——
日期:——
“β-Cyclodextrin nano-reactor”-catalyzed synthesis of 2<i>H</i>-chromene-2,3-dicarboxylates from in-situ-generated stabilized phosphorus ylides via intramolecular Wittig reaction in water
GRAPHICAL ABSTRACT Abstract A convenient one-pot synthesis of chromene derivatives from the three-component reaction of triphenylphosphine and dialkyl acetylenedicarboxylate and 2-hydroxybenzaldehyde derivatives in the presence of ß-cyclodextrin as a nano-catalyst is reported. In this reaction, ß-cyclodextrin (4.5 mole%) acts as a nano-catalyst as well as nano-reactor. This methodology is of interest