Synthesis, characterization and UV spectral studies of copolysilanes, image (R, R′ = Me, Et or Ph; R1 = Me or Ph) bearing carbosilyl side chains

A number of copolysilanes, View the MathML source{[RR2′Si(CH2)2SiMe]x[PhR1Si]1-x}n (R, R′ = Me, Et or Ph; R1 = Me (1–3); Ph (4–6)) bearing carbosilyl side chains have been synthesized by Wurtz coupling method and characterized by GPC, multinuclear (1H, 13C{1H}, 29Si{1H}) NMR and UV spectral studies. A detailed study of 29Si{1H} NMR spectra suggests that the copolysilanes 1–3 are comprised of segregated runs of PhMeSi and RMeSi (R = carbosilyl) units while 4–6 possess many different configurational and conformational environments. The UV spectra of these copolymers reveal a distinct absorption (λmax) at 312–352 nm due to σ–σ∗ transition and show a strong dependence on the polymer composition as well as nature of the appended sila substituents.