385367-84-0Relevant academic research and scientific papers
Diol-Ritter Reaction: Regio- And Stereoselective Synthesis of Protected Vicinal Aminoalcohols and Mechanistic Aspects of Diol Monoester Disproportionation
Ondari, Mark E.,Klosin, Jerzy,Kruper, William R.,Lysenko, Ivan,Thomas, Pulikkottil J.,Cheng, Kevin,Abboud, Khalil A.,Kruper, William J.
, p. 2063 - 2074 (2021/10/20)
The well-known epoxide-Ritter reaction generally affords oxazolines with poor to average regioselectivity. Herein, a mechanism-based study of the less known diol-Ritter reaction has provided a highly regioselective procedure for the synthesis of 1-vic-amido-2-esters from either terminal epoxides or 1,2-diols via Lewis acid-catalyzed monoesterification. When treated with a stoichiometric Lewis acid catalyst (BF3), these diol monoesters form dioxonium cation intermediates that are ring-opened with nitrile nucleophiles to form nitrilium intermediates, which undergo rapid and irreversible hydration to give the desired amidoesters. Diester byproduct formation is irreversible and appears to occur through disproportionation of diol monoester. With chiral epoxide starting materials, the formation of amidoester occurs with retention of configuration and no apparent erosion of optical purity as determined by single-crystal X-ray analyses and chiral chromatography, respectively. The direct access to chiral vic-amidoesters is especially practical with regard to the synthesis of antibacterial oxazolidinone analogues of the Zyvox antimicrobial family.
Studies on DMDO-mediated benzylidene acetal oxidation
Mycock, David K.,Sherlock, Alexandra E.,Glossop, Paul A.,Hayes, Christopher J.
body text, p. 6390 - 6392 (2009/04/06)
We have shown that dimethyldioxirane (DMDO) can be used to effect an oxidative partial deprotection of benzylidene acetals derived from both 1,2- and 1,3-diols to afford hydroxy benzoate products. A wide range of functional groups are tolerated, and good to excellent yields are usually observed. The reactions are easy to perform and produce little waste other than acetone.
Synthesis of optically active 2-hydroxy monoesters via-kinetic resolution and asymmetric cyclization catalyzed by heterometallic chiral (salen) Co complex
Li, Wenji,Thakur, Santosh Singh,Chen, Shu-Wei,Shin, Chang-Kyo,Kawthekar, Rahul B.,Kim, Geon-Joong
, p. 3453 - 3457 (2007/10/03)
The binuclear chiral (salen) Co complexes bearing Lewis acids of Al and Ga catalyze regio- and enantioselective ring opening of terminal epoxides with carboxylic acids. The ring opened product of epichlorohydrin with carboxylic acids followed by cyclization step in the presence of catalyst and base represent straightforward, efficient methods for the synthesis of enatiomerically enriched (>99% ee) valuable terminal epoxides. Strong synergistic effects of different Lewis acid of Co-Al and Co-Ga were exhibited in the catalytic process.
Chemo-enzymatic synthesis of levodropropizine
Caselli, Emilia,Tosi, Giovanni,Forni, Arrigo,Bucciarelli, Maria,Prati, Fabio
, p. 1029 - 1032 (2007/10/03)
Levodropropizine, an antitussive drug, was prepared in high enantiomeric excess in three steps, starting from dichloroacetone (2). Monosubstitution of 2 with sodium benzoate and subsequent baker's yeast reduction stereoselectively afforded the corresponding chlorohydrin in 73% ee, which was converted to levodropropizine and enantiomerically enriched up to 95% ee by fractional crystallisation.
