Synthesis, Characterization and Applications of a series of 1,3-bis- (trifluoromethyl aniline) imidazolium salts

Abstract

This thesis presents a novel contribution to knowledge via synthesis and characterization of new series of fluorinated imidazolium salts with different counter ions. The catalytic activity of new selenium, rhodium and copper(I) chloride of trifluoromethyl N-heterocyclic carbene were also investigated. In-depth study of the synthesis of fluorinated imidazolium salts via one-pot or multi-step reaction are reported (Chapters 3 and 4). Where the access into fluorinated imidazolium salts become straightforward with high yields and purity. Additionally, the electron properties of the σ-donation of the prepared fluorinated imidazolium tetrafluoroborate salts have been reported via NMR spectroscopy. A new series of fluorinated imidazolium selenide adducts are reported (Chapter 5). An investigation for the influence of changing different fluorinated substituents at the π accepting ability for the N-heterocyclic carbene are reported based on 77SeNMR spectroscopy. It was found that adding a trifluoromethyl (-CF3) group/s improved the accepting ability comparing to fluorine and trifluoromethoxy substituted systems. A novel series of Rh(cod)Cl(NHC) complexes containing NHC ligands possessing trifluoromethyl group/s are reported (Chapter 6). The catalytic activity for these complexes have been investigated in transfer hydrogenation of acetophenone derivatives, where the conversions for these types of complexes are consistent with the buried volume results. A series of novel air stable CuCl(NHC) containing NHC ligands with trifluoromethyl group/s are reported (Chapter 7). The complexes’ ability to catalyse A3-coupling reactions to synthesize propargylamines are studied using a range of aldehydes, where the majority of catalysts illustrate the capability to form the target compounds in moderate yield.