Diethyl chlorophosphate → (3-Oxo-2,3-dihydro-7-oxa-1,2-diaza-benzo[de]anthracen-10-ylmethyl)-phosphoramidic acid diethyl ester

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Reaction Steps

To a solution of compound 49 (0.5 mmol) in anhydrous DMF (20 mL) was added diethyl chlorophosphate (1.5 mmol). After 3 hours solution was concentrated in vacuo, and 50 mL of water was added. The aqueous layer was extracted with 30 mL of EtOAc twice. Organic layers were combined and washed with 30 mL of brine. Organic layer was dried with MgSO4. Solvent was removed to afford a white solid, which was recrystallized in 10% of EtOAc in hexanes to afford a white solid 54 in 50% yield. MS (ES−): 400; Mp: 222.3-224.5° C.; 1H-NMR (CDCl3, 400 MHz): 10.21 (s, 1H), 8.10 (d, J=2.5 Hz, 1H), 8.03 (d, J=7.5 Hz, 1H), 7.79 (t, J=8.0 Hz, 1H), 7.52 (d, J=8.0 Hz, 1H), 7.47 (dd, J=8.5 and 2.0 Hz, 1H), 7.22 (d, J=8.5 Hz, 1H), 4.12 (m, 6H), 1.32 (t, J=6.5 Hz, 6H); Anal. Calcd. for C19H20N3O5P.(0.3H2O): C, 56.10; H, 5.10; N, 10.33. Found: C, 56.00; H, 5.03; N, 10.13.

Provenance & Evidence