Phenylethenyl-substituted silicones via Heck coupling reaction

Systematic studies of several palladium complexes (Pd(OAc)2, [PdCl2(cod)], [Pd2(dba)3], [Pd(PPh3)4], [PdCl(SnCl3)(P{p-Tol}3)2], [Pd2Cl2(SnCl3)2(P{p-Tol}3)2]) as potential catalytic systems for arylation of vinylsiloxanes via Heck coupling reactions are described. Catalytic activity and selectivity were studied for a model reaction of trimethylvinylsilane with PhBr and m-ClC6H6Br and then the most effective systems were applied for functionalisation of tetramethyltetravinylcyclotetrasiloxane and poly(dimethylsiloxane-co-methylvinylsiloxane), leading to the silicone fluids having high refractive index (1.5–1.6).

Heck coupling process involving siloxane oligomeric and polymeric substrates, carried out in bulk is described, leading to high refraction index (1.5–1.6) silicone fluids. Effectiveness of various palladium catalytic systems is evaluated using model reaction of trimethylvinylsilane and aryl bromides.Figure optionsDownload as PowerPoint slide