Synthesis of Novel N-(4-Ethoxyphenyl) Azetidin-2-ones and Their Oxidative N-Deprotection by Ceric Ammonium Nitrate
作者:Aliasghar Jarrahpour、Maaroof Zarei
DOI:10.3390/12102364
日期:——
It is shown that the N-(p-ethoxyphenyl) group on beta-lactams can be oxidatively removed by ceric ammonium nitrate in good yield. Fourteen newN-(p-ethoxyphenyl)-2-azetidinones 8a-n were synthesized through standard [2+2] ketene-imine cycloadditions (Staudinger reaction). Treatment of these compounds with ceric ammonium nitrate yielded the N-dearylated 2-azetidinones 9a-n in good to excellent yields
Cerium(IV) Tetrabutylammonium Nitrate (CTAN): A Mild and Efficient N-dearylation Agent for Synthesis of N-unsubstituted 2-azetidinones
作者:Maaroof Zarei
DOI:10.3184/174751917x14902201357392
日期:2017.4
A simple and efficient protocol for the conversion of N-p-methoxyphenyl, N-p-ethoxyphenyl, N-p-methoxynaphthyl, N-3,4-dimethoxybenzyl and N-p-methoxybenzyl-2-azetidinones to N-unsubstituted 2-azetidinones using cerium(IV) tetrabutylammonium nitrate (CTAN) in dichloromethane is described. The method is compatible with a number of functional groups, and N-unsubstituted 2-azetidinones can be prepared
Efficient one-pot synthesis of 2-azetidinones from acetic acid derivatives and imines using methoxymethylene-N,N-dimethyliminium salt
作者:Aliasghar Jarrahpour、Maaroof Zarei
DOI:10.1016/j.tet.2010.05.009
日期:2010.7
A cheap, versatile and convenient method for synthesis of beta-lactams using methoxymethylene-N,N-dimethyliminium salt as an acid activator in Staudinger reaction is reported. This method is used for the preparation of monocyclic, spirocyclic, N-alkyl and three-electron-withdrawing group beta-lactams. The products are obtained in good to excellent yields. (C) 2010 Elsevier Ltd. All rights reserved.
Synthesis of <font>β</font>-Lactams from Acids and Imines Using Thiocarbonyldiimidazole
Abstract Thiocarbonyldiimidazole has been found to be an efficient acid activator for the synthesis of β-lactams by ketene-imine cycloaddition at room temperature. The experimental procedure is simple and results in excellent yields of the products. All products were characterized by spectral data and elemental analyses. GRAPHICAL ABSTRACT
Solid‐Solid Phase and Solvent‐Free Oxidative Removal of<i>N</i>‐(4‐Alkoxyphenyl) Groups of Monocyclic β‐Lactams with Ceric Ammonium Nitrate as a Cheap, Simple, and Efficient Method
作者:Aliasghar Jarrahpour、M. Zarei
DOI:10.1080/00397910801981326
日期:2008.5
Five N-(4-methoxyphenyl)- and five N-(4-ethoxyphenyl)-beta-lactams were prepared by ketene-imine [2+2] cycloaddition (Staudinger reaction). Then these 2-azetidinones were N-dearylated by grinding together with ceric ammonium nitrate without hazardous solvents in good to excellent yields. The solid-solid phase N-dearylation is easier, simpler, and more efficient than the general method in solution. The pure N-unsubstituted beta-lactams obtained by a nontedious workup and without further purification.