PIFA oxidizes hydroquinones and catechols to benzoquinones. In the presence of a nucleophile, 4-substituted phenols give the corresponding 4,4-disubstituted cyclohexadienone: J. Chem. Soc., Perkin 1, 1891 (1993); 2047 (1994), and refs. therein. In water, 1,4-dimethoxy aromatics undergo oxidative demethylation to p-quinones: Tetrahedron Lett.,42, 6899 (2001). In TFA, acetanilides can be hydroxylated in the p-position: J. Org. Chem., 67, 7424 (2002). Terminal alkynes are oxidized by PIFA to ɑ-hydroxy ketones: Tetrahedron Lett., 26, 3837 (1985). Primary amides undergo a Hofmann-like rearrangement to amines, avoiding the harsh conditions often required for the classical method: J. Org. Chem., 49, 4272, 4277 (1984); Synth. Commun., 18, 1615 (1988); Org. Synth. Coll., 8, 132 (1993). Promotes the azidation of alkyl groups of p-alkylanisoles with TMS azide: Tetrahedron Lett., 32, 4321 (1991);
