Triethylamine → 1-(4-Nitrophenyl)-D-proline

Participants

Reaction Conditions

Reaction Steps

Proline (3.5 g, 30.4 mmol), 4-iodonitrobenzene (7.2 g, 28.9 mmol), Pd(PPh3)4 (1.7 g, 5 mol %), copper iodide (0.3 g, 5 mol %), benzyltriethylammonium chloride (11.9 g, 52 mmol), triethylamine (8.3 ml, 60 mmol) and potassium carbonate (4.2 g, 30 mmol) were pre-mixed in DMF (60 ml)/water (6 ml). The reaction was heated at 80° C. for 8 hours. The DMF was removed in vacuo and the remaining black gum was dissolved in DCM, acidified with 2.0 N HCl (50 ml), extracted with DCM (3×100 ml), dried and solvent removed in vacuo to yield a black tar. The tar was dissolved in a minimum amount of DCM (7 ml) and loaded onto a 50 g silica column, the system was eluted with 20% EtOAc/isohexane, then 60% EtOAc/iso-hexane and finally 100% EtOAc. The title compound was obtained as an orange gum. NMR (299.954 MHz, CDCl3) 8.13 (d, 2H), 6.52 (d, 2H), 4.41 (d, 1H), 3.66 (t, 1H), 3.49 (q, 1H), 2.47-2.29 (m, 2H), 2.25-2.12 (m, 2H); m/z 237.

Provenance & Evidence