Pt- and Au-catalyzed oxidative cyclization of 2-ethenyl-1-(prop-2′-yn-1′-ol)benzenes to naphthyl aldehydes and ketones: catalytic oxidation of metal-alkylidene intermediates using H2O and H2O2

Abstract

2-Ethenyl-1-(prop-2′-yn-1′-ol)benzenes was cyclized through catalytic oxidation with PtCl₂/CO/H₂O and PEt₃AuCl/H₂O₂; the metal–naphthylidene intermediates were identified and oxygenated with water and H₂O₂, respectively; for the efficiency of cyclization, the Au catalytic system is superior to that of the PtCl₂-catalysis because of its compatibility toward diverse alcohol substrates including both internal alkynes and terminal alkynes.