2-Amino-3-methylpentanoic acid → HCID 18696373, compound

Participants

Reaction Steps

To a suspension of (dl)-isoleucine (2.03 g, 15.5 mmol) in toluene (40 mL) was added triethylamine (2.4 mL, 17.2 mmol). The mixture was heated to reflux temperature and bicyclo[2.2.1]hept-5-en-2,3-dicarboxylic anhydride (2.53 g, 15.5 mmol) was added. The reaction mixture was kept at reflux temperature and allowed to react for 4 hrs. After cooling to room temperature, the solvent was evaporated and the residue dissolved in H2O. The aqueous solution was washed with EtOAc, acidified with conc. HCl until pH=1, and extracted with EtOAc. The organic phase was washed with 5% HCl and brine and dried over Na2SO4. Removal of the solvent gave a white solid (3.72 g) which was recrystallized from EtOAc/hexane to yield the pure product as colorless crystals: mp=109° C.

Provenance & Evidence