Recent Advances in Transition-Metal-Catalyzed Selective C-H Alkoxycarbonyldifluoromethylation Reactions of Aromatic Substrates

Fluorine is well-known as a very special element. Approximately 30% of agrochemicals and 20% of all drugs contain fluorine; most of those compounds have unique functions in biochemistry, pharmacy, and bioscience and those containing alkoxycarbonyldifluoromethyl functional groups often have irreplaceable roles. Therefore, the selective introduction of alkoxycarbonyldifluoromethylated functional groups into various aromatic substrates has significant practical application. This review describes recent advances in selective alkoxycarbonyldifluoromethylation of aromatic substrates by using different catalytic strategies (cyclometalated ruthenium complex, transient regulating and visible-light-induced strategies). 1 Introduction 2 para-C-H Alkoxycarbonyldifluoromethylation of Aromatic Derivatives 2.1 Ruthenium Catalysis 2.2 Palladium Catalysis 2.3 Visible-Light Catalysis 2.4 Iron Catalysis 3 meta-C-H Alkoxycarbonyldifluoromethylation of Aromatic Derivatives 3.1 Ruthenium Catalysis 3.2 Palladium Catalysis 4 The Influence of Transition Metals and Directing Groups on Site Selectivity of Alkoxycarbonyldifluoromethylation 4.1 The Influence of Directing Groups on the Site Selectivity of Alkoxycarbonyldifluoromethylation 4.2 The Influence of Transition Metals on the Site Selectivity of Alkoxycarbonyldifluoromethylation 5 Conclusions