1: 78 percent / KOH / methanol; H2O / Heating 2: 90 percent / Et3N / CH2Cl2 3: 96 percent / H2O2 / tetrahydrofuran / Ambient temperature 4: 1.) NaIO4 / 2.) pyrolysis View Scheme

With  potassium hydroxide in  methanol; water  Heating;