Oxidation Carbonylative Polycondensation of Bisphenol

As stated above, the carbonylation oxidative polycondensation of bisphenol in the presence of transition metal-based catalysts leads to aromatic polycarbonate [scheme (18)] [6]. The reaction of bisphenol (HOArOH, e.g. Ar = p-C6H4 CMe2—C6H4—), carried out under CO and O2 pressure in a chlorohydrocarbon solvent under anhydrous conditions, using a group 8 metal-based catalyst (e.g. a PdBr2 complex) and a redox catalyst (e.g. Mn(II) (benzoinoxime)2, L vMn) in the presence of a base (e.g. 2,2,6,6,N-pentamethylpiperidine, R3N), involves most probably the pathway shown schematically below  

The Pd(0) species undergo bromination to Pd(II) species, PdBr2, via oxidation catalysed by a Mn(II) complex  

Note that the essential step of polycarbonate formation involves the reaction sequence shown below  

Although only low molecular weight polycarbonates in modest yield have been obtained by this method, it represents an interesting non-phosgene route to aromatic polycarbonates. 

Tindall, D., Pawlow, J. H. and Wagener, K. B., Recent Advances in ADMET 

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