128733-55-1Relevant 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.
Regioselective benzoylation of diols and carbohydrates by catalytic amounts of organobase
Lu, Yuchao,Hou, Chenxi,Ren, Jingli,Xin, Xiaoting,Xu, Hengfu,Pei, Yuxin,Dong, Hai,Pei, Zhichao
, (2016/07/06)
A novel metal-free organobase-catalyzed regioselective benzoylation of diols and carbohydrates has been developed. Treatment of diol and carbohydrate substrates with 1.1 equiv. of 1-benzoylimidazole and 0.2 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-ene (DB
2,2'-Bipyridinium chlorochromate/m-chloroperbenzoic acid-mediated cleavage of cyclic acetals to hydroxyesters
Luzzio, Frederick A.,Bobb, Rhiana A.
, p. 1733 - 1736 (2007/10/03)
Benzylidene acetals are cleaved to hydroxyesters by means of a reagent system composed of 2,2'-bipyridinium chlorochromate (BPCC) and m-chloroperbenzoic acid. Oxidative cleavage of a 4,6-O-benzylidene glucose derivative affords a 6-O-benzoyl derivative.
Organotin-Mediated Monoacylation of Diols with Reversed Chemoselectivity: A Convenient Synthetic Method
Reginato, Gianna,Ricci, Alfredo,Roelens, Stefano,Scapecchi, Serena
, p. 5132 - 5139 (2007/10/02)
The organotin-mediated monoesterification of unsymmetrical diols with reversed chemoselectivity has been explored to ascertain scope and limits of the method and to provide an easy and convenient synthetic procedure.The reaction has been performed on a set of substituted diols with some acylating agents usually employed as protecting groups.Two different procedures have been devised to obtain either the desired diol monoesters directly or the corresponding trialkylsilyl ethers as protected derivatives.The latter provides a convenient approach to the preparation of easily interconvertible diol monoesters.Also, the reaction has been optimized as a one-pot procedure, avoiding the isolation and purification of the stannylated intermediates.The reversed monoesterification method has been successfully applied to 1,2-, 1,3-, and 1,4-diols of primary-secondary, primary-tertiary, and secondary-tertiary types and to ether functions containing 1,2-diols.Within its limits, the described method represents the first direct one-pot monoesterification of diols at the most substituted site, allowing some remarkable achievements as (a) an almost regiospecific reversed monobenzoylation of some 1,2-diols, (b) the selective acylation of the tertiary hydroxyl of a primary-tertiary diol, and (c) a highly selective preparation of secondary pivalate of primary-secondary diols.
