Synthesis and Investigation of Perfluorinated Polystannanes

Two fluorinated tetraaryl stannanes, 1 and 2 were synthesized in good yields. X-ray crystallography revealed deviation from ideal tetrahedral geometry with C-Sn-C bond angles between 107.89°-112.7° for 1 and 104.69°-120.76° for 2. Dichlorides 4 and 5 were synthesized using a redistribution reaction between SnC1₄ and 1-2. These dichlorides also deviated from tetrahedral geometry with bond angles between 101.79°-128.44° for 4 and 99.23°-125.9° for 5. Polymerizaton of 4 and 5 by Wurtz coupling produced polymers 10 and 11. Absolute molecular weights in the range of 1.16 x 10⁵-2.92 x 10⁷ Da was estimated for 10 and 1.47 x 10⁵ Da for 11. UV/VIS spectroscopy gave values of 332 nm and 328 nm that are blue shifted to other polystannanes. The unexpected cleavage of a tin-aryl bond produced tin trihydrides 8 and 9. Polymerization of 8-9 produced the network polymers 12 and 13 with [wavelength]max values of 354 nm and 350 nm.

Synthesis and Investigation of Perfluorinated Polystannanes

Two fluorinated tetraaryl stannanes, 1 and 2 were synthesized in good yields. X-ray crystallography revealed deviation from ideal tetrahedral geometry with C-Sn-C bond angles between 107.89°-112.7° for 1 and 104.69°-120.76° for 2. Dichlorides 4 and 5 were synthesized using a redistribution reaction between SnC1₄ and 1-2. These dichlorides also deviated from tetrahedral geometry with bond angles between 101.79°-128.44° for 4 and 99.23°-125.9° for 5. Polymerizaton of 4 and 5 by Wurtz coupling produced polymers 10 and 11. Absolute molecular weights in the range of 1.16 x 10⁵-2.92 x 10⁷ Da was estimated for 10 and 1.47 x 10⁵ Da for 11. UV/VIS spectroscopy gave values of 332 nm and 328 nm that are blue shifted to other polystannanes. The unexpected cleavage of a tin-aryl bond produced tin trihydrides 8 and 9. Polymerization of 8-9 produced the network polymers 12 and 13 with [wavelength]max values of 354 nm and 350 nm.

Functional Polysilanes and their Optical, Chiroptical and Photoluminescence Properties

‘Polysilanes’ is an important class of inorganic polymers having Si-Si σ-conjugation along the backbone. They exhibit extraordinary electronic and photophysical properties and find suitable optoelectronics applications. They are typically synthesized by Wurtz coupling reaction of dichlorodialkylsilane or dichlorodiphenylsilane or dichloroalkylphenylsilane and their combinations under drastic reaction conditions by using sodium dispersion in boiling toluene. In such a drastic condition, no functional groups sustain with polysilane polymer. In order to achieve such functional materials, researchers have been interested in synthesizing functional polysilane with a different functional group like a chiral group, azobenzene containing chromophore and other heteroatoms in their main chain or side chain. Therefore, it is a very challenging task to synthesize polysilanes having effective functionality integrated with their structures. However, the modern technological demand of materials leads to efforts to obtain polymers having functional and multifunctional activity in a single material. In this review article, we cover the synthesis of polysilane with functional activity via pre-polymerization and post-polymerization with a functional group.

Microwave-assisted Wurtz coupling of methylphenyldichlorosilane in solvent-free conditions

This communication describes the synthesis of polymethylphenylsilane by the microwave-assisted coupling of methylphenyldichlorosilane using metallic sodium in solvent free conditions. The instant heating melts the sodium particles within the liquid methylphenyldichlorosilane and the polymerization reaction is achieved in minutes with total consumption of the monomer. The process is carried out in a high performance microwave reactor using the closed vessel operating facility which ensures control of the reaction parameters and highly reproducible results.