We report here a two-in-one strategy for the Pd(II)-catalyzed tandem C–H arylation/decarboxylative annulation between readily available cyclic diaryliodoniumsalts and benzoic acids. The carboxylic acid functionality can be used as both a directing group for the ortho-C–H arylation and the reactive group for the tandem decarboxylative annulation. By a step-economical double cross-coupling annulation
undergo ring closure and HF is eliminated. This photocyclodehydrofluorination (PCDHF) reaction is very useful to produce a wide range of selectively fluorinated polynucleararomatic hydrocarbons that possess a phenanthrene (or heterocyclic analogue of phenanthrene) substructure. These fluorinated products are of great interest in various aspects of the materials science.
A novel ligand-freePd-catalyzed cascade reaction between o-chlorobenzoic acids and cyclic diaryliodonium salts is reported. This one-pot procedure involves a carboxylic acid directed o-arylation followed by intramolecular decarboxylative annulation affording various valuable triphenylenes, which can be further transformed into diversified building blocks for material chemistry. For the first time
Palladium-Catalyzed Synthesis of Triphenylenes via Sequential C–H Activation and Decarboxylation
作者:Yuzhong Yang、Bang Zhou、Xiaoming Zhu、Guobo Deng、Yun Liang、Yuan Yang
DOI:10.1021/acs.orglett.8b02310
日期:2018.9.7
A novel tandem intermolecular decarboxylative coupling reaction of o-bromobenzoic acids and aryl iodides has been developed. The method affords a range of unsymmetrically triphenylenes and displays unique regioselectivity and broad substrate scope. Mechanistically, palladium/norbornene-catalyzed C–H activation and subsequent double decarboxylative coupling reactions were involved. Moreover, the triphenylenes