Chromans

Next, a competing functional group (OH in 4-mercaptophenol 2 i) was investigated, as phenols have been shown to form chromans or Friedel–Crafts allylation products under gold-catalysis with allylic alcohols. Pleasingly, the reaction proceeds chemoselectively at the thiophenol site, although the yield is somewhat lower than with other thiophenols (49 %, entry 9).