Trifluoroacetic acid → HCID 20719108, compound

Participants

Reaction Steps

To a solution of N-{[(S)-(5-Oxo-tetrahydrofuran-2-yl)carbonyl]}-L-leucine tertbutylester (800 mg, 2.67 mmols) in CH2Cl2 (3.0 ml) cooled at 0° C., was added freshly distilled anhydrous trifluoroacetic acid (0.5 ml). After a night at room temperature the solvent was evaporated at reduced pressure and the residue was dissolved in Et2O. By adding n-hexane the compound (2e) separated as a brown oil and was dried and decanted in high vacuum; 650 mg (100%); [a]D22=−7° (1, methanol); IR (CHCl3): 3413, 3036, 2957, 1787, 1725, 1678, 1526, 1172, 1191 cm−1; 1H-NMR (CDCl3): d 0.87 and 0.93 [two s, 6, CH2CH(CH3)2], 1.37-1.83 [m, 3, CH2CH(CH3)2], 2.06-2.73 (m, 4, ring CH2CH2), 4.30-4.63 (m, 1, ring CH), 4.67-4.92 (m, 1, aCH), 6.92 (d, 1, NH, J=8 Hz), 8.15 (s, 1, COOH). Calculated for C17H30N2O5.½ H2O (cyclohexylamine salt): C, 56.66; H, 8.89; N, 7.77. Found C, 57.00; H, 9.12; N 8.13%.

Provenance & Evidence