1: 81 percent / potassium tert-butoxyde / 96 h / Ambient temperature 2: 95 percent / 1N NaOH / tetrahydrofuran; H2O / 24 h / Ambient temperature 3: DDQ / tetrahydrofuran / 72 h / Ambient temperature 4: 93 percent / 1N NaOH / 24 h / Ambient temperature View Scheme

1: 81 percent / potassium tert-butoxyde / 96 h / Ambient temperature 2: 95 percent / 1N NaOH / tetrahydrofuran; H2O / 24 h / Ambient temperature 3: DDQ / tetrahydrofuran / 72 h / Ambient temperature 4: 91 percent / methanol; tetrahydrofuran / 24 h / Ambient temperature View Scheme