1: (R)-6-methyl-4-phenyl-3,4-dihydrochromen-2-one With sodium hydroxide in methanol; water T=70 - 80°C; 1 h; 2: dimethyl sulfate With tetrabutylammomium bromide in methanol; water T=40°C; 10 h; Title compound not separated from byproducts;

1.1: 88 percent / Rh(acac)(C2H4)2; (R)-Segphos / dioxane; H2O / 8 h / 60 °C 2.1: sodium hydroxide / H2O; methanol / 1 h / 70 - 80 °C 2.2: 96 percent / tetrabutylammonium bromide / methanol; H2O / 10 h / 40 °C View Scheme

1.1: 88 percent / Rh(acac)(C2H4)2; (R)-Segphos / dioxane; H2O / 8 h / 60 °C 2.1: sodium hydroxide / H2O; methanol / 1 h / 70 - 80 °C 2.2: 96 percent / tetrabutylammonium bromide / methanol; H2O / 10 h / 40 °C View Scheme