A compounds containing fluorene units, which have substituted alkyl chains and because of that some amphipilic character, were found to form stable monolayers (Langmuir-Blodgett layers) [1]. Because of the rigidity, planar rings and third-order nonlinear optical properties they can also form a novel pi-conjugated, processible, transparent and thermally stable copolymers. Materials obtaining from above compounds can be used in many electronic and optoelectronic devices [2].
2,7-bis(1,4-dioxane[2,3-c]thiophene)9,9-dialkylfluorene and 2,7-bis(thiophene)-9,9-dialkylfluorene have been synthesized via a Stillle-type coupling reactions [3] in which dibromodialkylfluorene was reacted with 2-(trimethylthin)thiophene or 2-metalated (1,4-dioxane[2,3-c])thiophene to give 9,9-dialkyl-2,7-bis(thiophene)fluorene or 2,7-bis(1,4-dioxane[2,3-c]thiophene)9,9-dialkylfluorene, using Pd(PPh3)2Cl2 or Pd(PPh3)4 as catalyst (Scheme 1). A series of bis(thiophenes)- and bis(dioxanethiophenes) based on fluorene rings were prepared for conductive material and characterized by 1H NMR and 13C NMR.
Further work is in progress in order to understand the role of disubstituted fluorenes in these reactions and also in polymer results.
The quantum-chemical calculations were performed to assess the usefulness of synthesised compounds for the electropolimerization. The structures and properties of synthesised molecules were determined theoretically. All examined molecules possess the planar three-ring fragment with negligibly different structural parameters.
1. LIU Y., LIU M., New Journal of Chemistry, 2002, 26, 180-183.

2. ZHAN X., LIU Y., ZHU D., LIU X., XU G., YE P., Chemical Physics Letters, 2002, 362, 165-169.

3. AFZALI A., BREEN T. L., KAGAN C. R., Chemistry of Materials, 2002, 14,1742-1746.