Esterification, Etherification, and Aldol Condensation Using Cathodically-Generated Organic Olate Anions
作者:Toshio Fuchigami、Takeshi Awata、Tsutomu Nonaka、Manuel M. Baizer
DOI:10.1246/bcsj.59.2873
日期:1986.9
Cathodic methods for the esterification of carboxylic acids and the etherification of phenol and benzenethiol under mild conditions were developed. The esterification was successfully carried out at room temperature by the reaction of alkylating reagents with cathodically-generated quaternary ammonium carboxylates. The etherification was similarly achieved using electrogenerated quaternary ammonium phenolate and halonitrobenzenes. A hindered phenolate anion cathodically-generated from 2,6-di-t-butyl-p-cresol remarkably promoted aldol condensation of aromatic ketones and aldehydes, and allowed subsequent Michael reaction to provide efficiently symmetrical 1,5-diketones.
Microwave-assisted, tetrabutylammonium hydroxide catalysed 1,4-addition of water to α,β-unsaturated ketones and α,β-ynones in aqueous solution
作者:Hyejeong Lee、Chul-Ho Jun
DOI:10.1039/c4ra09932j
日期:——
Microwave-assisted, tetrabutylammonium hydroxide catalysed 1,4-addition reactions of water to α,β-unsaturated ketones and α,β-ynones take place efficiently in water.
A tandem cross-coupling reaction of ketones with aldehydes has been achieved using barium hydride or isopropoxide as a promoter, in which barium enolates are generated in situ and then three successive reactions (aldol reaction-β-elimination-Michael addition) follow; this one-pot process is effective for obtaining symmetrical 1,5-diketones in good yields.
NaOH-Al2O3 Catalyzed Synthesis of 1, 3, 5-triarylpentane-1, 5-diones Derivatives Under Solvent-Free Condition and Crystal Structure of 3-(2', 4'-dichlorophenyl)-1, 5-diphenylpentane-1, 5-dione
作者:Xianqiang Huang、Qiu Feng、Yanliang Sun、Qingpeng He、Yong Wang
DOI:10.2174/157017812800233732
日期:2012.4.24
An efficient procedure for rapidly synthesizing the 1,3,5-triarylpentane-1,5-diones compounds using aromatic aldehydes and aromatic ketones as starting materials by tandem aldol reactions/Michael additions under NaOH/Al2O3 and the solvent-free conditions has been described. All compounds were characterized by IR, 1H NMR and elemental analysis. Additionally, the crystal structure of 3-(2’,4’-dichlorophenyl)-1,5-diphenylpentane-1,5-dione was obtained and determined by X-ray single-crystal diffraction. The protocol offers several advantages such as a simple, eco-friendly procedure and mild reaction conditions.
以芳香醛和芳香酮为起始原料,在 NaOH/Al2O3 和无溶剂条件下通过串联醛醇反应/迈克尔加成法快速合成 1,3,5-三芳基戊烷-1,5-二酮化合物的高效程序已经得到描述。所有化合物都通过红外光谱、1H NMR 和元素分析进行了表征。此外,还获得了 3-(2',4'-二氯苯基)-1,5-二苯基戊烷-1,5-二酮的晶体结构,并通过 X 射线单晶衍射测定了其晶体结构。该方案具有程序简单、环保、反应条件温和等优点。
Half-sandwich Ru(II)-thioamide complexes as catalysts for one pot synthesis of aromatic 1,5-diketones
作者:Haritha Rajasekaran、Peter Jerome、Eugene V. Eliseenkov、Vadim P. Boyarskiy、Nattamai Bhuvanesh、Ramasamy Karvembu
DOI:10.1016/j.jorganchem.2022.122322
日期:2022.5
Four Ru(II)-arene thioamide complexes of the type [(η6-cymene)Ru(PPh3)(L)]+ (L = bidentate monoanionic thioamide ligand) have been synthesized and isolated as their hexafluorophosphate salts. All these complexes are fully characterized by spectroscopic methods. Molecular structures of the ligands (HL2 and HL3) and complex (3) were determined by single crystal X-ray crystallography. The ligands coordinated
[( η 6 -伞花烃)Ru(PPh 3 )(L)] + ( L = 双齿单阴离子硫代酰胺配体)类型的四种Ru(II)-芳烃硫代酰胺配合物 已合成并分离为它们的六氟磷酸盐。所有这些配合物都通过光谱方法充分表征。配体 (HL2 和 HL3) 和复合物 ( 3 ) 的分子结构通过单晶 X 射线晶体学确定。配体通过酚O和硫代酰胺S原子与Ru中心配位。在 KO t Bu存在下,所有四种配合物均作为催化剂在芳香酮和醇的一锅法合成 1,5-二酮中进行了测试,并通过 GC/GC-MS/ 1对产物进行了分析。核磁共振氢谱。配合物1和2充当催化剂以产生 1,5-二酮,而配合物3和4催化反应形成烷基化酮。反应范围扩大到各种取代的醇和酮,用催化剂 1制备 1,5-二酮。