hydrogen; palladium on activated charcoal in methanol 18 h; Ambient temperature; Yield given;

1: 1.) oxalyl chloride, dimethyl sulfoxide, 2.) Et3N / 1) CH2Cl2, -78 deg C, 15 min; 2) CH2Cl2, -78 deg C, 50 min 2: 1.) sodium cyanoborohydride / 1) MeOH, AcOH, rt, 2.5 h; 2) dioxane 3: H2 / Pd/C / methanol / 18 h / Ambient temperature View Scheme

1: 1.) sodium cyanoborohydride / 1) MeOH, AcOH, rt, 2.5 h; 2) dioxane 2: H2 / Pd/C / methanol / 18 h / Ambient temperature View Scheme