1: 9,9-dimethyl-4,5-bis(diphenyl-phosphino)xanthene; caesium carbonate; tris-(dibenzylideneacetone)dipalladium(0) / 1,4-dioxane / 18 h / |Inert atmosphere; |Reflux 2: hydrogenchloride / diethyl ether / 18 h / 25 °C View Scheme