1: DCC / tetrahydrofuran / -15 deg C, 1.5 h then to r.t., overnight 2: 1.) BH3*SMe2; 2.) CAN / 1.) THF, r.t., 3 h; 2.) 60percent aq. CH3CN, 0 deg C, 5 min 3: 98 percent / NH4Cl / methanol / Ambient temperature View Scheme