1: With iron; acetic acid 4 h; 2: With sodium carbonate in water; ethyl acetate

1.1: N,N-dimethyl-formamide / 18 h / 95 °C 2.1: sodium periodate / water; tetrahydrofuran / 6 h / 20 °C 3.1: titanium tetrachloride / dichloromethane; diethyl ether / 1 h / -78 - -50 °C 3.2: 1 h / -50 °C 4.1: Dess-Martin periodane / dichloromethane / 16 h 5.1: acetic acid; iron / 4 h View Scheme

1.1: sodium periodate / water; tetrahydrofuran / 6 h / 20 °C 2.1: titanium tetrachloride / dichloromethane; diethyl ether / 1 h / -78 - -50 °C 2.2: 1 h / -50 °C 3.1: Dess-Martin periodane / dichloromethane / 16 h 4.1: acetic acid; iron / 4 h View Scheme

1: Dess-Martin periodane / dichloromethane / 16 h 2: acetic acid; iron / 4 h View Scheme