Tetrahydrofuran → N-(4-Naphthalen-2-ylmethyl-3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-5-yl)-oxalamic acid

Participants

Reaction Steps

To a suspension of N-(4-Naphthalen-2-ylmethyl-3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-5-yl)-oxalamic acid methyl ester, K-67 (95 mg,) in methanol (2.0 mL), 1.0 M NaOH (0.5 mL) was added followed by THF (2.0 mL) resulting in a clear solution. Reaction was stirred at room temperature for 30 minutes and then concentrated to remove the solvents. The residue was taken in water (2.0 mL), acidified with 1.0 M HCl and extracted with ethyl acetate (5.0 mL×4). Combined extracts were washed with water (5.0 mL), dried (brine, Na2SO4) and concentrated to afford N-(4-Naphthalen-2-ylmethyl-3-oxo-3,4-dihydro-2H-benzo [1,4]oxazin-5-yl)-oxalamic acid, A51 (69 mg). 1H NMR (CDCl3) 4.66 (s, 2H), 5.21 (s, 2H), 7.02 (m, 2H), 7.07 (d, J=8.5 Hz, 1H), 7.14 (br s, 1H), 7.33 (br s, 2H), 7.50 (s, 1H), 7.65 (m, 3H), 8.69 (s, 1H). MS (ESI−) Calcd. for: 376.4; Found: 375.5 (M−H).

Provenance & Evidence