Recent Strategies in Non-Heme-Type Metal Complex-Catalyzed Site-, Chemo-, and Enantioselective C–H Oxygenations
Tatsuya Uchida, Daiki Doiuchi
Abstract
Abstract C–H bonds are ubiquitous and abundant in organic molecules. If such C–H bonds can be converted into the desired functional groups in a site-, chemo-, diastereo-, and enantio-selective manner, the functionalization of C–H bonds would be an efficient tool for step-, atom- and redox-economic organic synthesis. C–H oxidation, as a typical C–H functionalization, affords hydroxy and carbonyl groups, which are key functional groups in organic synthesis and biological chemistry, directly. Recently, significant developments have been made using non-heme-type transition-metal catalysts. Oxygen functional groups can be introduced to not only simple hydrocarbons but also complex natural products. In this paper, recent developments over the last fourteen years in non-heme-type complex-catalyzed C–H oxidations are reviewed. 1 Introduction 2 Regio- and Chemo-Selective C–H Oxidations 2.1 Tertiary Site-Selective C–H Oxidations 2.2 Secondary Site-Selective C–H Oxidations 2.3 C–H Oxidations of N-Containing Molecules 2.4 C–H Oxidations of Carboxylic Acids 2.5 Chemo- and Site-Selective Methylenic C–H Hydroxylations 3 Enantioselective C–H Oxidations 3.1 Desymmetrizations through C–H Oxidations 3.2 Enantiotopic Methylenic C–H Oxygenations 4 Conclusion