1: 60 percent / KOH / methanol; H2O / 4 h / Heating 2: 80 percent / tetrahydrofuran / 1.) r.t. 2.) reflux 2 h View Scheme

potassium hydroxide in methanol; water 4 h; Heating;

1: 60 percent / KOH / methanol; H2O / 4 h / Heating 2: 80 percent / tetrahydrofuran / 1.) r.t. 2.) reflux 2 h 3: 72 percent / 1) PTS monohydrate / acetic acid / 1.) 30 min, 0 deg C 2.) 30 min, r.t. View Scheme