hydrogenchloride Yield given. Multistep reaction. Yields of byproduct given;

1: 5,6-O-isopropylidene-D-mannono-1,4-lactone With sodium periodate in water 2: dimethyl methoxycarbonylmethanephosphonate With potassium carbonate

1.1: NaIO4 / H2O 1.2: K2CO3 2.1: 95 percent / DIBAL-H / tetrahydrofuran View Scheme