Efficient and Simple Approaches Towards Direct Oxidative Esterification of Alcohols
作者:Ritwika Ray、Rahul Dev Jana、Mayukh Bhadra、Debabrata Maiti、Goutam Kumar Lahiri
DOI:10.1002/chem.201403786
日期:2014.11.17
The present article describes novel oxidative protocols for directesterification of alcohols. The protocols involve successful demonstrations of both “cross” and “self” esterification of a wide variety of alcohols. The cross‐esterification proceeds under a simple transition‐metal‐free condition, containing catalytic amounts of TEMPO (2,2,6,6‐tetramethyl‐1‐piperidinyloxy)/TBAB (tetra‐n‐butylammonium
Electrochemical esterification reaction of alkynes with diols <i>via</i> cleavage of carbon–carbon triple bonds without catalyst and oxidant
作者:Pei-Long Wang、Hui-Zhi Shen、Hui-Hui Cheng、Hui Gao、Pin-Hua Li
DOI:10.1039/d0gc02193h
日期:——
as it is catalyst-free, oxidant-free, and additive-free and shows atom-economy. This is the first example of an electrochemical reaction via cleavage of carbon–carbon triple bonds. Meanwhile, this is also the first example of a carbon–carbon triple bond cleavage reaction of alkynes with diols.
acyclic acetals to the corresponding hydroxyalkyl carboxylic esters and simple esters, respectively. 2-Iodoxybenzoic acid (IBX) in the presence of tetraethylammonium bromide was employed for the reaction in aqueous media. The salient features of the protocol include short reaction time, environmentally benign reagents and solvent, and moderate to high yields. o-iodoxybenzoic acid - acetals - oxidations
Plant activators are a novel kind of agrochemicals that could induce resistance in many plants against a broad spectrum of diseases. To date, only few plant activators have been commercialized. In order to develop novel plant activators, a series of benzo-1,2,3-thiadiazole-7-carboxylate derivatives were synthesized, and the structures were characterized by H-1 NMR, IR, elemental analyses, and HRMS or MS. Their potential systemic acquired resistance as plant activators was evaluated as well. Most of them showed good activity, especially, fluoro-containing compounds 3d and 3e, which displayed excellent SAR-inducing activity against cucumber Erysiphe cichoracearum and Colletotrichum lagenarium in assay screening. Field test results illustrated that compounds 3d and 3e were more potent than the commercial plant activator, S-methyl benzo[1,2,3]thiadiazole-7-carbothioate (BTH) toward these pathogens. Further, the preparation of compound 3d is more facile than BTH with lower cost, which will be helpful for further applications in agricultural plant protection.
Facile oxidative hydrolysis of acetals to esters using hypervalent iodine(III)/LiBr combination in water
作者:Waraporn Panchan、Supanimit Chiampanichayakul、Deanna L. Snyder、Siriporn Yodbuntung、Manat Pohmakotr、Vichai Reutrakul、Thaworn Jaipetch、Chutima Kuhakarn
DOI:10.1016/j.tet.2010.01.098
日期:2010.4
The combination of (diacetoxy)iodobenzene (Phl(OAc)(2), DIB) and lithium bromide (LiBr) efficiently oxidized cyclic and acyclic acetals to the corresponding hydroxyalkyl carboxylic esters and simple esters in good to excellent yields The merits of this reaction are that it employs commercially available and non-explosive hypervalent iodine(III) reagent, water as the solvent, a short reaction tune, and mild reaction conditions (C) 2010 Elsevier Ltd All rights reserved