Surfactant-aided catalytic copolymerization of carbon monoxide with ethene in water as a solvent

The perfectly alternated ethene-carbon monoxide co-polymerisation to poly(1-oxotrimethylene) was in the last decade an important topic in the field of catalysis [1]. Since we have focalized our research on the influence of solvent on this reaction [2], we are also interested to study the possibility to use green solvents such as water. In fact, water is cheap, readily available, non-toxic, non-flammable, and safe to environment [3]. The use of water may be interesting for many other reasons, in particular for the possibility to obtain very high molecular weight polymers [2]. The catalytic polymerization is efficiently carried out in methanol by using the [Pd(OAc)2(DPPP)] complex in the presence of an acid (ptoluenesulfonic, TsOH) [1]. By replacing methanol with water it is necessary to use the more expensive but solvable [Pd(OAc)2(DPPP-S)] complex as precursor (DPPP–S is the sulfonated ligand) [4]. As an alternative to the sulfunated ligand we propose to carry out the catalysis in water with the aid of surfactants. Here we report our preliminary results on the preparation of alt- poly(1-oxo-trimethylene) by using the [Pd(OAc)2(DPPP)] complex in water containing a surfactant above the critical micelle concentration. The performance of various surfactants are highlighted.