10.1021/jo802028n
The research focuses on the synthesis and characterization of quaterthiophene derivatives, specifically 4T, Oct-4T, and Tol-4T, which are p-type organic semiconductors based on a central 2,2'-bithiophene core with terminal indeno[1,2-b]thiophene units. The study employs Stille and Miyaura-Suzuki couplings for the synthesis, involving reactants such as 2,2'-bithiophenes and derivatives of indeno[1,2-b]thiophene. The electronic properties of these compounds are analyzed through cyclic voltammetry, UV-vis absorption, and fluorescence emission spectroscopy. The thermal stability and solubility of the compounds are also evaluated, and their potential in organic field-effect transistors (OFETs) is explored. The experiments utilize various analytical techniques including mass spectrometry (MALDI-TOF and ESI+ HRMS), nuclear magnetic resonance (NMR), and X-ray diffraction to confirm the structure and purity of the synthesized compounds. The research also details the preparation and characterization of OFETs fabricated from these materials, reporting on their hole-mobility and on/off ratios.
10.1039/b302462h
The research focuses on the development of a novel and direct synthetic method for alkylated 2,2'-bithiophene derivatives, which are significant precursors for oligo- and poly-thiophenes due to their valuable physical properties like electrical conductivity and electroluminescence. The study presents a nonmetallic oxidative coupling of alkylthiophene derivatives using a combination of hypervalent iodine(III) reagent, phenyliodine bis(trifluoroacetate) (PIFA), and boron trifluoride diethyl etherate (BF3·Et2O). The purpose of this research was to find a more direct and efficient route to bithiophenes without the need for transition metal catalyzed coupling reactions, which are typically required for their synthesis. The conclusions drawn from the study indicate that the PIFA-BF3·Et2O system successfully led to the formation of 2,2'-bithiophenes in moderate to good yields, providing a novel and direct route to these important compounds without the need for additional activation of thiophene monomers. This method offers a safer alternative to heavy metal reagents and addresses the challenge of selectively obtaining bithiophenes over polythiophenes, which is a common issue with conventional oxidative methods.
