Hydrazine hydrate (1:1) → t-butyl (R)-2-(2-aminoethylamino)-3-methylbutyrate

Participants

Reaction Steps

t-Butyl (R)-2-(2-(1,3-dioxo-1,3-dihydroisoindol-2-yl)ethylamino)-3-methylbutyrate (6.60 g; 19.05 mmol) was dissolved in ethanol (100 ml). Hydrazine hydrate (4.62 ml; 95.25 mmol) was added, and the reaction mixture was heated under reflux for 2 h. The solid was filtered off with suction through kieselguhr and washed with ethanol (100 ml). The solvent was removed and the residue was partitioned between saturated NaHCO3 solution (150 ml) and CH2Cl2 (150 ml). The phases were separated and the aqueous phase was extracted with CH2Cl2 (2×; 100 ml). The combined organic phases were dried over MgSO4. Removal of the solvent under reduced pressure resulted in t-butyl (R)-2-(2-aminoethylamino)-3-methylbutyrate (4.60 g; 19.05 mmol). MS: 217.25 (M+H); Rt: 0.69 min (method: gradient 0 min 96% H2O (0.05% TFA) 2.0 min 95% acetonitrile, 95% acetonitrile to 2.4 min, 4% acetonitrile 2.45 min; flow rate 1 ml/min; column 0.4 μL (YMC J'sphere ODS H80 20X2 1.4μ); 30° C.)

Provenance & Evidence