以矽烷基為間隔含三種不同染色基團之高分子的合成及光物理性質

Abstract

利用銠金屬催化將雙乙炔和雙矽氫化合物進行矽氫化反應合成一系列以矽烷基為間隔包含三種發光基團交錯排列的雙乙烯基高分子[(donor)n-SiMe2-(acceptor-1)m-SiMe2-(acceptor-2)-SiMe2]。以鎳金屬催化雙硫縮醛化合物與格林納試劑的偶合反應可得到乙烯基矽基醚，再由氫化鋁鋰進行還原反應，得到相對應的雙矽氫化合物。經由Sonogashira偶合反應可合成雙乙炔單體。此合成策略可提供ㄧ個方便且有效的方法合成具有位向選擇性的高分子，而高分子鏈內可包含多種發光基團並且各發光基團間的比例可精確地控制，另外也經由其光譜研究其光物理性質。 在此包含三種發光基團的系統中，以聯苯為能量給體，二苯乙烯為受體一，三苯二乙烯為受體二，而矽基團在聚合物中則扮演絕緣體的角色，並連接各發光基團，給受體之間的比例為1:1:1、1:2:1及2:2:1，各發光基團在聚合物中有規則地交替連接，當激發給體的最大吸收波長時，由螢光放射光譜可以觀察到受體二的螢光放射強度明顯較給體大的多，說明了高分子內可以有效地進行能量轉移，其效率皆在80%以上。

A series of silylene-spaced copolymers containing alternating aryl groups [(donor)n-SiMe2-(acceptor-1)m-SiMe2-(acceptor-2)-SiMe2] were synthesized by rhodium-catalyzed hydrosilylation of bis-alkynes with bis-silylhydrides. Bis-silylhydrides were prepared by nickel-catalyzed olefination of the corresponding aryl bisdithioacetals with Grignard reagent (Me2(iPrO)SiCH2MgCl) followed by LiAlH4 reduction. Bis-alkynes were obtained by Sonogashira reaction. This strategy provided a powerful arsenal to construct a regioselective polymeric backbone containing several chromophores with desired ratios of donors and acceptors. In these three-chromophore system, biphenyl was used as an energy donor; stilbene as the first acceptor and terphenylenedivinylene as the second acceptor. The silylene group was an insulating spacer as well as a linker among chromophores. The photophysical properties were also examined in details.