Synthesis of a Polyisobutylene-farnesyl Pyrophosphate Macroinitiator for In-vitro Synthesis of Polyisobutylene-b-cis-1,4-polyisprene

Research in biochemistry revealed that the biosynthesis of polyisoprenoids and terpenes proceeds through cationic polymerization. Recently, Puskas et al. proposed that natural rubber (cis-1,4 polyisoprene, NR) biosynthesis also proceeds via a carbocationic mechanism.1 To develop better understanding of this process, a synthetic macroinitiator analogue of nature's initiator, farnesyl pyrophosphate (FPP), will be employed in an in vitro NR biosynthesis system to synthesize PIB-block-NR in vitro, in collaboration with the United States Department of Agriculture (USDA). This work discusses the first four steps of the synthesis of the polyisobutylene-farnesyl pyrophosphate (PIB-FPP) macroinitiator. The structures of the macroinitiator and its intermediates were confirmed by nuclear magnetic resonance (NMR) spectroscopy and matrix-assisted laser desorption/ionization - time of flight (MALDI-TOF) mass spectroscopy.
References: 1. Puskas, J. E.; Gautriaud, E.; Deffieux, A.; Kennedy, J. P. Progress in Polymer Science 2006, 31, 533-548.