Investigation of catalytic properties of some benzimidazoles

Benzimidazoles and their derivatives have been extensively studied because they are present in many naturally occurring products and various drugs. On the other hand, benzimidazole based N-heterocyclic carbenes (NHCs) have been exhibited many interesting properties that make them valuable as ligand used as an alternative to the more expensive phosphine ligands in many catalytic reactions.Concerns for maximal use of raw materials and minimal generation of waste products stimulate the search for appropriate catalyst for the reactions both in laboratory and industry.High-speed synthesis with microwaves has attracted a considerable amount of attention in recent years. The efficiency of microwave flash heating in dramatically reducing reaction times is just one of the many advantages.It has been known that, many organometallic compound having benzimidazole moiety exhibit efficient catalytic properties.Due to these reasons, in this thesis, carbene precursors benzimidazole salts were synthesised and their catalytic properties were investigated in Suzuki, Heck and Ring closure reactions with and without microwave. The catalytic activities of the benzimidazole compounds were determined in the selected reactions using by GC-MS techniques. The optimum catalytic activities of the benzimidazole salts in Suzuki ve Heck reactions were obtained 5 minutes microwave irradiation.Structure of all new compounds synthesised in this work were identified by 1H-NMR, {1H}-13C-NMR, FT-IR spectroscopic techniques, and micro analysis.