A compounds containing carbazole units, which have substituted alkyl chains and because of the 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 -conjugated, processible, transparent and thermally stable materials. Most frequently a carbazoles molecules are placed in side chains of polymer (copolymer) [2]. Earlier experiences with synthesis similar structures [3] are allowed to suppose that a polymer which contain in main chain carbazoles unit between two pyrroles or thiophens, combains in a one chain electroconductive and electroluminescent properties conjugated polymers and photoactive chromophore characteristics [2] and could be applied in a large number of sensors and photonic devices.
3,6-bis(1,4-dioxane[2,3-c]thiophene)-N-alkylcarbazole and 3,6-bis(thiophene)-N-alkylcarbazole have been synthesized via a Stillle-type coupling reactions [4] in which dibromoalkylcarbazole was reacted with 2-(trimethylthin)thiophene or 2-metalated (1,4-dioxane[2,3-c])thiophene to give 3,6-bis(thiophene)-N-alkylcarbazole or 3,6-bis(1,4-dioxane[2,3-c]thiophene)-N-alkylcarbazole, using Pd(PPh3)2Cl2 or Pd(PPh3)4 as catalyst.
A series of bis(thiophenes)- and bis(dioxanethiophenes) based on carbazole 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 carbazole in these reactions and also in polymer results.
1. Y. Liu., M. Liu., New Journal of Chemistry, 2002, 26, 180-183.
2. X. Zhan, Y. Liu, D. Zhu, X. Liu, G.Xu, P. Ye, Chemical Physics Letters, 2002, 362, 165-169.
3. J.Sołoducho, S.Roszak A. Chyla, K. Tajchert, New Journal of Chemistry, 2001, 25, 1175-1181.
4. A. Afzali, T. L. Breen, C. R. Kagan, Chemistry of Materials, 2002, 14,1742-1746.
|