Hypervalent Iodine Reagents in the Synthesis of Flavonoids and Related Compounds

Hypervalent iodine compounds have proved to be very useful reagents to bring about various oxidative transformations including (i) α-functionalization of carbonyl compounds, (ii) oxidation of phenols, and (iii) oxidative rearrangement of ketones and α,β- unsaturated ketones. These reactions find interesting applications in the development of newer and convenient approaches for the synthesis of flavonoids. This review focuses on the use of most common three hypervalent compounds, namely iodobenzene diacetate, [hydroxy(tosyloxy)iodo]benzene, and [bis-trifluoroacetoxy(iodo)]benzene in the synthesis of cis/trans-3-hydroxyflavanones, 3-hydroxyflavones (flavonols), flavones, isoflavones and related compounds.