α,ω-Functionalized Poly(2-Oxazoline)s Bearing Hydroxyl and Amino Functions

• Published in: Macromolecular chemistry and physics 2011-08, Vol.212 (16), p.1815-1824
• Main Authors: Reif, Michael, Jordan, Rainer
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; lipopolymers; model membranes; Organic polymers; Physicochemistry of polymers; Polymerization; polyoxazoline; Preparation, kinetics, thermodynamics, mechanism and catalysts; protective group chemistry; telechelic polymers
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.201100276

Novel α,ω‐functionalized amphiphilic lipopolymers are prepared that are composed of a proximal lipid moiety and a hydrophilic poly(2‐oxazoline)‐based (POx) polymer chain. The synthesis begins from bifunctional lipoinitiators, which are asymmetrically protected as tert.butyldiphenylsilyl (TBDPS) ethers, followed by cationic living ring‐opening polymerization of 2‐oxazolines in a one‐pot multistep reaction. This results in polymers with defined terminal end groups and narrow molar mass distributions. All protective groups involved can be readily cleaved in a single step reaction keeping the structure of the polymer intact, giving access to (lipo)polymers with a variety of defined identical or chemical orthogonal α,ω‐functionalities. The synthetic strategy is a versatile tool for the preparation of defined polymer–drug or polymer–protein conjugates or asymmetric functionalized model lipid membranes for the quantitative study of membrane‐associated phenomena such as transmembrane transport and cell adhesion/recognition. α,ω‐Functionalized poly(2‐oxazoline)s with either two alcohol or an alcohol and amine endgroup are accessible from diols using suitable protective group chemistry. This synthetic approach gives access to telechelic poly(2‐oxazoline)s for the construction of next generation biomimetic membrane constructs as well as polymer–drug conjugates (polymer therapeutics).