Imidazole → 3,5-Xylyloxyacetic acid

Temperature

0 °C

Referring to FIG. 42, a mixture of PPh3 (0.8 g, 3.0 mmol) and imidazole (0.3 g, 4.5 mmol) in DCM (20 mL) was stirred for 30 min at 0° C. Then a solution of Br2 (0.7 g, 4.5 mmol) in DCM (5 mL) was added. The mixture was kept at 0° C. for 10 min and compound 1 (0.3 g, 1.5 mmol) was added. The reaction mixture was stirred at 0° C. for 10 min (monitored by TLC and UPLC analysis). The mixture was washed with diluted HCl solution (20 mL×2), saturated aqueous NaHSO3 (20 mL) and brine (20 mL), respectively. The organic layer was concentrated under reduced pressure and the residue was purified by flash column chromatography on silica gel (petroleum ether/EtOAc=100:1 to 30:1) to afford the title compound 2 (0.2 g, 40% yield); 1H NMR (300 MHz, CDCl3): δ 7.41 (d, J=8.4 Hz, 2H), 7.10 (d, J=8.4 Hz, 2H), 4.51 (s, 2H), 2.86-2.81 (m, 2H), 2.68-2.65 (m, 2H), 2.07-2.06 (m, 1H).

1. waitThe mixture was kept at 0° C. for 10 min
2. stirringThe reaction mixture was stirred at 0° C. for 10 min (monitored by TLC and UPLC analysis)
3. washThe mixture was washed with diluted HCl solution (20 mL×2), saturated aqueous NaHSO3 (20 mL) and brine (20 mL)
4. concentrationThe organic layer was concentrated under reduced pressure
5. customthe residue was purified by flash column chromatography on silica gel (petroleum ether/EtOAc=100:1 to 30:1)

ORD record

ord-ee1ee57e5bb64f7eaf44117d3f97d2d7

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09309283B2