C2- and C3-Symmetric Meta-substituted Thienyl Benzenes: A Comparative Synthetic and Structural Study
Date of Award
2007
Degree Type
Thesis
Degree Name
Master of Science
Program
Chemistry
Supervisor
Dr. Nathan Jones
Abstract
Suzuki, Stille and Kumada coupling approaches to the syntheses of various C1- and C3- symmetric thienylbenzene compounds (A and B, respectively) are systematically compared. Novel routes are reported for the syntheses of C3-symmetric compounds using Kumada (n = 0) and Stille (n = 1) coupling reactions. Potentiodynamic treatment of these compounds produces polymers whose properties as a function of the length of the thienyl substituent (n= 1 vs. n = 2), and of cross-linking (C2 vs. C3), are compared. The solidstate structures of C2- and C3-symmetric (n = 1) compounds are also discussed. Furthermore, the syntheses of novel meta-substituted benzenes that bear both thiophene and halogen groups are reported (C, n = 0 or 1). Further elaboration of the third meta position using Kumada, Stille and Sonogashira coupling methods gives a family of C2-symmetric compounds of the general structure l,3-bis(thienyl)-5-R-benzene, where R is either an electron-donating or -withdrawing group. The physical and optical properties of these compounds are compared using spectroscopic (UV-visible absorption and fluorescence) and electrochemical measurements. The anodic peak potentials (Epa) obtained for these compounds do not correlate with their σm Hammett parameters.
Recommended Citation
Cornacchio, Angelica Lee Petrina, "C2- and C3-Symmetric Meta-substituted Thienyl Benzenes: A Comparative Synthetic and Structural Study" (2007). Digitized Theses. 4670.
https://ir.lib.uwo.ca/digitizedtheses/4670