1. Room Temperature Ring-Opening Polymerization of cyclo-Phosphazenes
Christopher A. Reed, Center for S and P Block Chemistry, University of California, Riverside, CA 92521
Using 31P NMR, end groups and intermediates in the ring-opening polymerization of cyclo-N3P3Cl6 have been observed for the first time. See color coding in Figure. This was made possible by the discovery of trialkylsilyl carboranes as a room temperature catalysts for a reaction normally carried out at 200 ºC.
“monomer”
polymer
catalyst
5 min
30 min
60 min
90 min
120 min
cyclo-pentamer cyclo-hexamer
150 min
cyclo-tetramer
180 min