Reduction of ketones by carbene catalyzed

N-heterocyclic carbenes has been widely used in organometallic chemistry and coordination chemistry for 30 years. Numereous saturated and unsaturated stable N-heterocyclic carbenes have been prepared. The key concept of these materials in coordination chemistry is the active metal center. In comparasion, NHC showed better catalytic activity than the corresponding phosphine ligands , not only due to their strong ? -donating and weak ? -accepting abilities but also the easy of controlling steric effects on nitrogen atoms.Reduction of organic compounds is the most important synthetic step both industrially and scientifically. Hydrogen transfer reaction takes place in the presence of metal catalyst is very important since, it can be used in place of gaseous hydrogen as hydrogen donor thus it is economic, mild and ecological.Up to date, the use carbene complexes in this field is limited, improving the use of these catalyst will be very helpful. For this reason new carbene precursors and their metal complexes have been prepared and tested for reduction of ketones in this work.This work could be summarized in three chapters.1)In the first chapter, 1,3-dialkylimidazolinium 2a-f and 1,3-dialkil-1,3,4,5-tetrahidroprimidinium (6a-f) NHC precursors were prepared and their structure were elucidated by spectroscopic techniques.2)NHC complexes, obtained by the interaction of a monodentate carbene precursors and a base, reacted with [RuCl2(p-cimene)]2 complexes and the corresponding complexes 4a-e were prepared and their structure was investigated with proper techniques.3)Ru-NHC complexes (4a-e) have been tested transfer hydrogenation of ketones and catalytic activities were investigated.