1: sodium phosphate, tetrabutylammonium periodate / CHCl3 / 24 h 2: 44 percent / sodium phosphate, m-CPBA / CHCl3 / 43 h / Ambient temperature 3: 30 percent / NaBH4 / methanol / 1.) 0 deg C, 12 h, 2.) RT, 24 h 4: 67 percent / sodium phosphate, tetrabutylammonium periodate / CHCl3 / 14 h / Ambient temperature 5: 75 percent / tetrabutylammonium fluoride / tetrahydrofuran / 1 h / Ambient temperature View Scheme

Multi-step reaction with 2 steps 1: 79 percent / NaBH4, CeCl3*7H2O / ethanol / 1.5 h / 0 - 20 °C2: Et3N, DMAP / CH2Cl2 / 50 h / Heating  

With  tetrabutylammonium (meta)periodate; sodium salt of phosphorous acid in  chloroform 24 h;  Yield given;   

Multi-step reaction with 2 steps 1: sodium phosphate, tetrabutylammonium periodate / CHCl3 / 24 h2: 44 percent / sodium phosphate, m-CPBA / CHCl3 / 43 h / Ambient temperature  

Multi-step reaction with 3 steps 1: sodium phosphate, tetrabutylammonium periodate / CHCl3 / 24 h2: 44 percent / sodium phosphate, m-CPBA / CHCl3 / 43 h / Ambient temperature3: 30 percent / NaBH4 / methanol / 1.) 0 deg C, 12 h, 2.) RT, 24 h  

Multi-step reaction with 4 steps 1: sodium phosphate, tetrabutylammonium periodate / CHCl3 / 24 h2: 44 percent / sodium phosphate, m-CPBA / CHCl3 / 43 h / Ambient temperature3: 30 percent / NaBH4 / methanol / 1.) 0 deg C, 12 h, 2.) RT, 24 h4: 67 percent / sodium phosphate, tetrabutylammonium periodate / CHCl3 / 14 h / Ambient temperature