2004 年 72 巻 3 号 p. 159-164
The silylene-germylene copolymer with the SiSiGe ordered sequences was successufully synthesized in 49% yield by the electroreductive polymerization of bis(chlorodimethylsilyl)dibutylgermane, which was prepared by the electroreductive cross-coupling reaction of chlorodimethylsilane with dichlorodibutylgermane followed by the chlorination of the Si-H bonds. The resulting copolymer having 3900 of the number average molecular weight showed a characteristic strong UV absorption bands (λmax) at 300 nm, and the extinction coefficients (εmax) per dibutylgermylene and dimethylsilylene units were calculated to be 14000. On the other hand, the electroreductive homo- and copolymerization of dibutyldichlorosilane or dibutyldichlorogermane with dichlorodimethylsilane were also carried out using Mg electrodes to give the corresponding copolymers in 6-44% yield. The number average molecular weights were 3000-4600. The copolymers showed λmax at 308 and 286 nm. The εmax per dibutylsilylene, dibutylgermylene or dimethylsilylene units were calculated to be 6300 and 1600. The εmax value of copolymer with SiSiGe sequences was found to be much higher than those of copolymers having random sequences. A large difference of the εmax values between the silylene-germylene copolymers is probably due to the conformational difference of the polymer main chain.
