反应详情

In an oven dried flask was added 2-methoxy-4-chlorobenzoic acid (1.0 g, 0.0054 mol), thionyl chloride (0.77 mL, 0.010 mol) and a drop of DMF and the reaction was refluxed for 2 h. The thionyl chloride was then distilled off and benzene (20 mL, 0.2 mol) and aluminum trichloride (0.676 g, 0.00507 mol) was added to the reaction mixture and the reaction was stirred at room temp for 1 h. The crude reaction mixture was poured onto ice and conc HCl (15 mL). The organic layer was separated and the aqueous layer extracted with EtOAc. The combined organic phases were washed with 5% aq NaOH solution, water and dried (Na2SO4). The organic phase was concentrated in vacuo to give a residue which was purified by silica gel chromatography, eluting with 2% EtOAc in hexane. 1H NMR (400 MHz, CDCl3): δ=3.74 (s, 3H), 7.00 (d, J=1.77 Hz, 1H) 7.05 (dd, J=8.08, 1.77 Hz, 1H), 7.32 (d, J=8.08 Hz, 1H), 7.41-7.48 (m, 2H), 7.54-7.60 (m, 1H), 7.74-7.83 (m, 2H). MS (ES+): m/z 246.83 (100)[MH+]. HPLC: tR=3.66 min (Open Lynx polar—5 min).

1. customIn an oven dried flask
2. distillationThe thionyl chloride was then distilled off
3. customThe crude reaction mixture
4. customThe organic layer was separated
5. extractionthe aqueous layer extracted with EtOAc
6. washThe combined organic phases were washed with 5% aq NaOH solution, water
7. dry with materialdried (Na2SO4)
8. concentrationThe organic phase was concentrated in vacuo
9. customto give a residue which
10. customwas purified by silica gel chromatography
11. washeluting with 2% EtOAc in hexane
12. customHPLC: tR=3.66 min (Open Lynx polar—5 min)