1: 93 percent / pyridine / 0.5 h / steam bath 2: 91.1 mg / tert-butyl chromate reagent, glacial AcOH, Ac2O / tetrachloroethene / 0.75 h / 86 - 88 °C 3: hydrogen / 10percent Pd on carbon / ethyl acetate / 0.75 h / Ambient temperature; atmospheric pressure 4: 1.) perchloric acid, acetic anhydride, 2.) bromine, epichlorohydrine / 1.) ethyl acetate, room temperature, 15 min, 2.) CCl4, 0 deg C, 10 min 5: 1.) semicarbazide hydrochloride, sodium acetate, 2.) aq. pyruvic acid / 1.) dioxane, water, room temperature, 2 h, 2.) overnight View Scheme

1: 93 percent / pyridine / 0.5 h / steam bath 2: 91.1 mg / tert-butyl chromate reagent, glacial AcOH, Ac2O / tetrachloroethene / 0.75 h / 86 - 88 °C 3: hydrogen / 10percent Pd on carbon / ethyl acetate / 0.75 h / Ambient temperature; atmospheric pressure 4: 1.) perchloric acid, acetic anhydride, 2.) bromine, epichlorohydrine / 1.) ethyl acetate, room temperature, 15 min, 2.) CCl4, 0 deg C, 10 min 5: 1.) semicarbazide hydrochloride, sodium acetate, 2.) aq. pyruvic acid / 1.) dioxane, water, room temperature, 2 h, 2.) overnight View Scheme

1: 100 percent / sodium borohydride / ethanol / 1 h / Ambient temperature 2: 93 percent / pyridine / 0.5 h / steam bath 3: 91.1 mg / tert-butyl chromate reagent, glacial AcOH, Ac2O / tetrachloroethene / 0.75 h / 86 - 88 °C 4: hydrogen / 10percent Pd on carbon / ethyl acetate / 0.75 h / Ambient temperature; atmospheric pressure 5: 1.) perchloric acid, acetic anhydride, 2.) bromine, epichlorohydrine / 1.) ethyl acetate, room temperature, 15 min, 2.) CCl4, 0 deg C, 10 min 6: 1.) semicarbazide hydrochloride, sodium acetate, 2.) aq. pyruvic acid / 1.) dioxane, water, room temperature, 2 h, 2.) overnight View Scheme

1: hydrogen / 10percent Pd on carbon / ethyl acetate / 0.75 h / Ambient temperature; atmospheric pressure 2: 1.) perchloric acid, acetic anhydride, 2.) bromine, epichlorohydrine / 1.) ethyl acetate, room temperature, 15 min, 2.) CCl4, 0 deg C, 10 min 3: 1.) semicarbazide hydrochloride, sodium acetate, 2.) aq. pyruvic acid / 1.) dioxane, water, room temperature, 2 h, 2.) overnight View Scheme

semicarbazide-hydrochloride; sodium acetate; 2-oxo-propionic acid 1.) dioxane, water, room temperature, 2 h, 2.) overnight; Yield given. Multistep reaction;

1: 1.) perchloric acid, acetic anhydride, 2.) bromine, epichlorohydrine / 1.) ethyl acetate, room temperature, 15 min, 2.) CCl4, 0 deg C, 10 min 2: 1.) semicarbazide hydrochloride, sodium acetate, 2.) aq. pyruvic acid / 1.) dioxane, water, room temperature, 2 h, 2.) overnight View Scheme

water in methanol T=40°C; pH 9, also reaction in the presence of 2-hydroxypropyl-β-cyclodextrin; Rate constant;

1: NaBH4 / methanol 2: KOH / methanol View Scheme