Hydrochloric Acid → Ncx-701

To a solution of 4-acetamidophenol (Paracetamol) (0.96 g, 6.30 mmol) TEA (0.64 g, 6.3 mmol) and DMAP (0.77 g, 6.3 mmol) in CH2Cl2/THF (9:1, 30 ml) kept at 0° C., under stirring and under nitrogen atmosphere, a solution of 4-(nitrooxy)butanoic acid pentafluorophenyl ester (2.0 g, 6.30 mmol) (Preparation 2) in CH2Cl2 (10 ml) was added. The resulting solution was kept under stirring for further 240 minutes at room temperature. The reaction mixture was poured in a pH 3 buffer solution (about 50 ml), acidified with HCl 1 N to pH 3-4 and extracted with CH2Cl2 (2×50 ml). The organic phase washed with brine (100 ml), dried on sodium sulfate and evaporated under vacuum. Purification by Flash chromatography of the residue (n-hexane/AcOEt 1:1) gave the title compound as a white solid (1.52 g, 84%). M.p., NMR and HPLC analysis were consistent with data reported in the literature.

1. customkept at 0° C.
2. stirringunder stirring for further 240 minutes at room temperature
3. extractionextracted with CH2Cl2 (2×50 ml)
4. washThe organic phase washed with brine (100 ml)
5. customdried on sodium sulfate
6. customevaporated under vacuum
7. customPurification by Flash chromatography of the residue (n-hexane/AcOEt 1:1)

ORD record

ord-2bc112fffc57443b85a5775d0a1c717b

Source dataset

uspto-grants-2010_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07723529B2