Cobalt carbonyl-catalyzed carbonylation of functionalized aziridines to versatile β-lactam building blocks
作者:Nicola Piens、Kristof Van Hecke、Dieter Vogt、Matthias D'hooghe
DOI:10.1039/c7ob00832e
日期:——
carbonylation of different classes of non-activated aziridines with diverse substitution patterns was investigated. Special attention was devoted to selectivity issues and reaction optimization. This study resulted in the regio- and stereospecific synthesis of 24 novel β-lactam target structures in high yields on a multigram scale. The synthetic potential of the newly obtained azetidin-2-ones was illustrated
Cationic ring-opening polymerization of <i>N</i>-benzylaziridines to polyamines <i>via</i> organic boron
作者:Ge-Ge Gu、Tian-Jun Yue、Wei-min Ren
DOI:10.1039/d2cc06817f
日期:——
reports the synthesis of cyclic polyamines via the cationic ring-opening polymerization (CROP) of N-benzylaziridines initiated by tris(pentafluorophenyl)borane. The debenzylation of these polyamines afforded water-soluble polyethylenimine derivatives. The electrospray ionization mass spectrometry and density functional theory results revealed that the CROP proceeded via the activated chain end intermediates
Quaternary Ammonium Bromide Functionalized Polyethylene Glycol: A Highly Efficient and Recyclable Catalyst for Selective Synthesis of 5-Aryl-2-oxazolidinones from Carbon Dioxide and Aziridines Under Solvent-Free Conditions
作者:Ya Du、Ying Wu、An-Hua Liu、Liang-Nian He
DOI:10.1021/jo800269v
日期:2008.6.1
A quaternary ammonium bromide covalently bound to polyethylene glycol (PEG, MW = 6000), i.e., PEG(6000)-(NBu3Br)(2), was found to be an efficient and recyclable catalyst for the cycloaddition reaction of aziridines to CO2 under mild conditions without utilization of additional organic solvents or cocatalysts. As a result, 5-aryl-2-oxazolidinone was obtained in high yield with excellent regioselectivity. The catalyst worked well for a wide variety of 1-alkyl-2-arylaziridines. Besides, the catalyst could be recovered by centrifugation and reused without significant loss of catalytic activity and selectivity.