Phosphine‐Catalyzed 1,6‐Addition and Tandem Addition/Self‐Aldol Condensation Reactions of Para‐Quinone Methides with Thiols

Abstract Phosphine‐catalyzed chemodivergent reactions of para ‐quinone methides ( p ‐QMs) affording a wide variety of diarylmethyl thioether derivatives have been reported. In the transformation presented in this work, P(4‐FC 6 H 4 ) 3 catalyzed the direct 1,6‐addition of p ‐QMs with thiols, whereas P(4‐MeC 6 H 4 ) 3 promoted the tandem addition/self‐aldol condensation reactions of p ‐QMs with 1,4‐dithiane‐2,5‐diol. Moreover, some of the obtained products were screened against cancer cell lines HepG2, NB4, and K562, and one was found to inhibit the proliferation of all the tested cancer cell types.