Silylative coupling polycondensation

In contrast to the above-mentioned monomers, l,4-bis(dimethylvinylsiloxy)butane in the presence of [RuHCl(CO)(PPh3)3] (1 mol%) under analogous conditions undergoes silylative coupling polycondensation to yield mainly siloxylene-alkylene-vinylene oligomers (isolated yield 60%). Only very small amounts of intramolecular reaction product (2,2,4,4-tetramethyl-3-... 

SILYLATIVE COUPLING POLYCONDENSATION (SCP) VS. ADMET POLYMERIZATION OF DIVINYLSUBSTITUTED SILICON COMPOUNDS... 

The a,co bis(vinyldimethyl)silylalkanes also undergo de-ethenated Silylative Coupling Polycondensation (SCP) to yield poly(silylene, alkylene, vinylene)s under optimum conditions and in the presence of the given catalyst according to the equation 5 [25]. 

In the silylative coupling reactions of olefins and dienes with vinylsubsti-tuted silanes, ruthenium catalysts, containing initially or generating in situ Ru-H/Ru-Si bonds, catalyze polycondensation of divinylsubstituted silicon compounds to yield unsaturated silylene (siloxylene, silazanylene)-vinyl-ene-alkenylene (arylene) products (Eq. 112). For recent results see Refs. [177, 178] and for reviews see Refs. [6,7,117,118]. 

In the presence of a ruthenium complex, divinylsilicon compounds can also undergo co-polycondensation with dienes, for example, 1,4-divinylbenzene [178,179]. For recent reviews on the silylative coupling (co)polycondensation see Refs. [6,7,117,118]. 

On the other hand, divinyl-substituted organosilicon compounds in the presence of ruthenium and rhodium complexes containing or generating M-H and M-Si (M = Ru, Rh) bonds undergo competitive silylative coupling cyclization and polycondensation to give a mixture of oligomers and... 

Therefore, the aim of this work was to synthesize new silacyclic and oligomeric organosilicon compounds containing easily modifiable Sl-O-R bonds, via competitive silylative coupling cyclization and polycondensation of divlnyl-substltuted silyl ethers in the presence of ruthenium hydride complex. 

The high conversion of monomers and the distribution of products in the time of reaction catalyzed by [RuHCl(CO)(PPh3)3], performed under mild conditions (toluene, 110°C or 80 °C), show that o.w-bis(dimethylvinylsiloxy)alkanes undergo silylative coupling cycllzation/polycondensation according to Scheme 3. 

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