Hydrochloric Acid → HCID 57451841, compound

The mixture of 2-ethoxy-6-formylphenylboronic acid (80 g, 0.41 mol), NaOH (16.5 g, 0.41 mol) and CTAB (7.7 g, 20 mmol) in H2O (100 mL) and THF (500 mL) was stirred for 0.5 h at room temperature After dropwise addition of nitromethane (14 mL, 2.4 mol), the reaction mixture was stirred at room temperature for 3 h. Then the cyclization was afforded by adding the diluted HCl (2 N) to pH=2 and then extracted with EtOAc (3×300 mL). The combined organic layers were washed with brine (250 mL), dried over anhydrous Na2SO4 and concentrated to dryness in vacuo. The residue was purified by column chromatography on silica gel to give the target compound as white solid (92 g, yield 94%). 1H NMR (400 MHz, DMSO-d6 δ 9.06 (s, 1H), 7.46-7.43 (t, 1H), 7.07-7.05 (d, 1H), 6.89-6.87 (d, 1H), 5.71-5.69 (m, 1H), 5.31-5.27 (m, 1H), 4.57-4.51 (m, 1H), 4.12-4.07 (m, 2H), 1.34-1.30 (t, 3H).

1. stirringthe reaction mixture was stirred at room temperature for 3 h
2. customThen the cyclization was afforded
3. extractionextracted with EtOAc (3×300 mL)
4. washThe combined organic layers were washed with brine (250 mL)
5. dry with materialdried over anhydrous Na2SO4
6. concentrationconcentrated to dryness in vacuo
7. customThe residue was purified by column chromatography on silica gel

ORD record

ord-7dc20eb26aa64b7a94d0cab5bc778ca2

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08703742B2