Application Of Transition Metal Iridium Complex In Alkylation Reaction

The alkylation structure of organic compounds is widely existed in medical pharmaceutical and agricultural products. The alkylation is an important transformation for carbon-carbon bond formation in organic synthesis. The traditional method for alkylation of organic compounds involves coupling of their enolates with alkyl halides under a certain condition. Although very useful, this approach suffers from the use of toxic alkyl halides and the formation of waste inorganic salts is not easy to realize industrialization. In recent years, with alcohols as alkylating reagent alkylation reaction began to concern. Alcohols are preferred alkylating reagents because they are less expensive than alkyl halides, non-toxic, and their alkylation produces only water as a byproduct, which is conducive to large-scale industrial application. In the past decade, alkylation with alcohols employing the so-called " borrowing hydrogen " methodology has emerged as a powerful and green process for new bond formations. However, these systems required relatively high loadings of precious metal catalysts and high reaction temperatures. For some substrates with functional groups also has a certain limitation. These flaws affect its application value, to a certain extent. Our group focused on addressing these shortcomings through developing a new type efficient transition metal catalysts. This thesis discussed some meaningful results, including:1. We developed a new PN P-type pincer iridium catalyst for the a-alkylation of amides with primary alcohols. This reaction provides a convenient, general, and environmentally method to realize the α-alkylation of amides. So this reaction will have a higher application value in organic synthesis.2. Investigation of the a-alkylations of ketones with primary alcohols catalyzed by "[Ir(COD)Cl]2/DPPP/KOH". Compared with the previously reported, this reaction under mild conditions with low catalyst loadings and broad functional-group tolerance.3. We developed a new and high efficiency catalyst " Ir-PNN " used in the a-alkylation of amides with primary alcohols. In the reaction, this catalyst showed a higher efficiency. Morever, it also can be applied to other alkylation of organic compounds.