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An iron(III)-catalyzed C-3 functionalization of flavones has been achieved using tert-butyl peroxybenzoate (TBPB)/potassium persulphate (K2S2O8) oxidant combinations with a suitable solvent. In the presence of iron(III)/tert-butyl peroxybenzoate/potassium persulphate, the reaction of flavones in cycloalkanes afforded exclusive C-3 cycloalkylation via Csp2 –Csp3 coupling, whereas the solvent N,N-dialkylformamide provided C-3 amidation via Csp2 –Csp2 coupling. Under identical reaction conditions just by switching the solvent to chlorobenzene, C-3 methylated flavones were obtained where tert-butyl peroxybenzoate (TBPB) served as the source of the methyl group.

An unprecedented palladium(II)-catalyzed biomimetic aliphatic acyl (-COR) group transfer was observed from acyl-α-peroxycoumarins to the ortho CH sites of directing arenes. Here, the CH activation is associated with a concomitant acyl group transfer via a Pd(II)-catalyzed, redox-neutral process. While methods for ortho aroylation (-COAr) are well documented ortho acylation (-COR) processes are scarce, hence the present redox-neutral method is most ideal for o-acylation of directing substrates.

An efficient copper‐catalyzed protocol has been developed for the synthesis of carbamates from dialkylformamides and phenols possessing directing groups such as benzothiazole, quinoline and formyl at the ortho‐position. In this chelation assisted approach, C-O bond formation takes place via a Cross Dehydrogenative Coupling (CDC) between the formyl C-H of dialkylformamide and phenolic O-H in the presence of copper(II)acetate/aqueous tert‐butyl hydroperoxide. Under identical reaction conditions, salicylic acid derivatives underwent amidation with the carboxylic group rather than formamidation of the phenolic OH. The use of a cheap and environmentally benign catalyst along with the tolerance of a wide range of functional groups makes this an easy, phosgene‐free route to carbamates.