以5,5'-二(三甲基硅烷基)-3,3'-联硫基苯基-2,2'-二甲醛为先驱物,通过分子内有效地获得了2,7-二(三甲基硅烷基)-噻吩并[3,2- e ]苯并噻吩麦克默里反应。同时,另外两个意外化合物1,2,5,6(5)-四-(三甲基甲硅烷基)-1,2,5,6(2,3)-四噻吩-环辛烷3(Z),7 (Z)-二烯和2,7-二(三甲基甲硅烷基)噻吩并[3,2 - e ]-苯并噻吩-4-醇是副产物。描述了所有三种标题化合物的晶体结构。
Comparison of Ullmann/RCM and Ullmann/Bis-hydrazone Coupling Reactions; New Access to Benzodithiophenes for Dye-Sensitized Solar Cell and Thiahelicene Applications
摘要:
The use of CuTC (Liebeskind's catalyst), followed by methylenation and ring-closing metathesis, or bis-hydrazone coupling reactions is described. This approach establishes an alternative non-photochemical synthesis of the strategically important 1,2-b:4,3-b' BDT regioisomer, which has previously been underused in applications such as dye-sensitized solar cells and nonlinear optics because of the difficulty of synthesis on a large scale.
We describe the synthesis of trialkylsilyl-substituted trans-1,2-bis(thieno[3,2-e]benzothiophene-2-yl)ethenes as suitable soluble precursors for the preparation of the corresponding silylated tetrathia[7]helicenes, which, in turn, can be desilylated or transformed into dihalogen-substituted derivatives through electrophilic substitution of silyl substituents. X-ray structural studies showed that the