Polymerization of Cyclic Depsipeptides, Ureas and Urethanes

The majority of poly(ester-amide)s are prepared by the polycondensation of dicar-boxylic acids with diols and diamines or, for example, polymerization reactions in combination with amino acids, lactones and lactams. During recent decades, many polymers have been prepared, and the synthesis and properties of these materials have recently been reviewed [1]. 

Based on the large number of natural amino acids present, and also commercially available, a large number of cyclic monomers can be prepared. The 

Handbook of Ring-Opening PolymerizaHon. Edited by P. Dubois, O. Coulembier, and J.-M. Raquez Copyright 2009 WiLEY-VCH Veriag GmbH Co. KGaA, Weinheim ISBN 978-3-527-31953-4 

The preparation of morpholine-2,5-diones derivatives via route A was first described by Chadwick and Pascu [5], who found that upon dry-heating N-((2 R,S)-bromopropionyl]-glycine, (6 R,S)-methyhnorpholine-2,5-diones was formed. This 

PMB = pentamethylbenzyl. First step N,N -dicydohexylcarbodiimide/4-dimethyl-aminopyridine (DCC/DMAP). Second step HBr/Acetic acid. Third step Triethylamine, N,N -dicyclohexylcarbodiimide/ 1-hydroxybenzo-triazole (DCC/HOBt). 

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Part 2 includes chapters on specific classes of cyclic monomers and their polymerization mechanisms and kinetics, their main (co)polymer architectures and related products, as well as current and future applications. Hence, siloxane-con-taining and sulfur-nitrogen-phosphorus-containing polymers are described in Chapters 3 and 4, respectively, while the polymerization of cyclic depsipeptides, ureas and urethanes, of polyethers and polyoxazolines, and of polyamides are detailed in Chapters 5, 6 and 7, respectively. Chapters 9, 10, 11 and 12 include details of polyesters prepared from either P-lactones, from dilactones, from larger lactones and from polycarbonates, while the polymerization of cycloalkanes is described in Chapter 13. It should be noted that, slightly out of place . Chapter 8 covers the subject of ring-opening metathesis polymerizahon. 

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