Regioselective preparation of functional aryl ethers and esters by stepwise nucleophilic aromatic substitution reaction

Functional aryl ethers bearing mono- and di-substituted azo compounds, allyl functionalities, vinyl phenyl moieties, trifluoromethyl (CF3) groups, etc. were prepared by nucleophilic substitution reaction of 2,3,4,5,6-pentafluorobenzonitrile (PFBN) in a stepwise manner at room temperature in dipolar aprotic solvents in a regioselective manner. Mono substituted aryl ether further underwent two more substitutions at ortho and ortho′ positions either with the same or different phenoxides. However, para substituted monoesters as well as para-ether-ortho-ester obtained by using carboxylates as (one of the) nucleophiles did not undergo any further displacement. The synthetic strategy described here is useful for making various functional materials such as lubricants, liquid crystals, curing agents, pigments and superhydrophobic materials.