Preparation of Lactams from Cyclic Anhydrides via N‐Carboxyanhydride Intermediates
作者:Simon N. Smith、Stephen J. Connon
DOI:10.1002/ejoc.202100751
日期:2021.10.26
Cyclic anhydrides can be readily converted to ring-contracted lactams after sequential silylazidation, protonolysis, Curtius rearrangement and catalysis of ring closure by DMAP, in an operationally simple procedure. Succinic anhydrides do not form ring-contracted β-lactams but instead generate β-N-carboxyanhydrides which serve as activated analogues of β-amino acids of use in β-peptide and polymer
Access to Amphiphilic <i>Cis</i>-Configurated Polyamide-3 Using Alcohols as Initiators
作者:Olga Maiatska、Alexander Belkin、Helmut Ritter
DOI:10.1021/acs.macromol.5b00272
日期:2015.4.28
The synthesis of polyamide-3 from 4a,5,8,8a-tetrahydro-1H-benzo[d][1,3]oxazine-2,4-dione (beta-NCA, 1) using methanol, dye (Disperse Red 13), and poly(ethylene glycol) as initiator is described. The ring-opening polymerization under release of CO2 produces polyamides-3 with definite terminal groups, high purity, and relatively narrow dispersity. This route was used for preparation of block copolymers from as an example.