1.1: pyridinium chlorochromate; molecular sieves 4 Angstroem / CH2Cl2 / 2 h / 20 °C 2.1: potassium tert-butoxide / tetrahydrofuran / 0.33 h / 20 °C 2.2: tetrahydrofuran / 0.5 h / cooling 3.1: NaOH / methanol; tetrahydrofuran; H2O / 1.5 h 3.2: potassium tert-butoxide / tetrahydrofuran / 0.83 h View Scheme

1.1: pyridinium chlorochromate; molecular sieves 4 Angstroem / CH2Cl2 / 2 h / 20 °C 2.1: potassium tert-butoxide / tetrahydrofuran / 0.33 h / 20 °C 2.2: tetrahydrofuran / 0.5 h / cooling 3.1: NaOH / methanol; tetrahydrofuran; H2O / 1.5 h 3.2: potassium tert-butoxide / tetrahydrofuran / 0.83 h View Scheme

1.1: pyridinium chlorochromate; molecular sieves 4 Angstroem / CH2Cl2 / 2 h / 20 °C 2.1: potassium tert-butoxide / tetrahydrofuran / 1.83 h / cooling 2.2: tetrahydrofuran / 1 h / cooling 3.1: NaOH / methanol; tetrahydrofuran; H2O / 1 h / 20 °C 3.2: potassium tert-butoxide / tetrahydrofuran / 0.5 h / cooling View Scheme

1: pyridinium chlorochromate; molecular sieves 4 Angstroem / CH2Cl2 / 2 h / 20 °C View Scheme

1.1: pyridinium chlorochromate; molecular sieves 4 Angstroem / CH2Cl2 / 2 h / 20 °C 2.1: potassium tert-butoxide / tetrahydrofuran / 0.42 h / cooling 2.2: tetrahydrofuran / 0.75 h / cooling 3.1: NaOH / methanol; tetrahydrofuran; H2O / 1 h / 20 °C 3.2: potassium tert-butoxide / tetrahydrofuran / 1.17 h / cooling View Scheme

1.1: pyridinium chlorochromate; molecular sieves 4 Angstroem / CH2Cl2 / 2 h / 20 °C 2.1: potassium tert-butoxide / tetrahydrofuran / 0.33 h / 20 °C 2.2: tetrahydrofuran / 0.5 h / cooling 3.1: NaOH / methanol; tetrahydrofuran; H2O / 1.5 h 3.2: potassium tert-butoxide / tetrahydrofuran / 0.83 h View Scheme