One-pot construction of sterically challenging and diverse polyarylphenols via transition-metal-free benzannulation and their potent in vitro antioxidant activity.

This paper reports the novel and efficient one-pot synthesis of highly functionalized polyarylphenols from readily available 1,3-diarylpropan-2-ones and chalcones or cinnamaldehyde derivatives via benzannulation under transition-metal-free and aerobic conditions. This benzannulation proceeds through cascade Michael addition/intramolecular aldol/tautomerization/oxidation. This protocol produces various tetra- and tri-aryl substituted phenols in moderate to good yield. The synthesized compounds exhibited potent antioxidant activities compared to the standard BHT.