A versatile approach to the synthesis of polyphosphazene derivatives via the thiol-ene reaction

The thiolene radical addition reaction has been successfully used to synthesize polyphosphazene derivatives. Poly[bis(allylamino)phosphazene] with pendant allyl groups was reacted with different thiol reagents under UV irradiation. These thiol reagents include 1-pentanethiol, 3-mercaptopropionic acid, 3-mercapto-1,2-propane-diol, and 2,3,4,6-tetra-O-acetyl-1-thio-beta-D-glucopyranose. 1H NMR analyses confirm that the allyl polyphosphazene can be quantitatively modified by the mercaptans. In total, 100% conversion of the allyl groups was reached in <60 min toward the first three mercaptans, whereas about 80% conversion of the allyl groups was reached after 120-min reaction toward the thioglucose. This method is a facile route for the synthesis of functional polyphosphazenes without the needs for protection/deprotection procedures. (C) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012