1: HOAc, NaBH3CN / methanol / 1.) -78 deg C, 2 h, 2.) r.t., 20 h 2: 99 percent / H2 / 20percent Pd(OH)2/C / methanol / 24 h / 3102.9 Torr View Scheme

sodium cyanoborohydride; acetic acid in methanol 1.) -78 deg C, 2 h, 2.) r.t., 20 h;