反应详情

A solution of 4-chlorobenzyl bromide (Lancaster Chemical) (10.0 g, 48.6 mmol) in 40 mL ether was added under nitrogen to a suspension of magnesium turnings (Alpha Chemical Inc.) in ether (60 mL) over 10 minutes. The suspension was stirred for 2 h and the supernatant was cannulated under nitrogen into another round bottom flask fitted with a magnetic stirrer bar. Then 2,4-dichlorobenzonitrile (7.0 g, 40.5 mmol) in 65 mL ether was slowly added under nitrogen to the Grignard solution and the mixture was stirred over night at room temperature. The imine precipitated out of solution and the mixture was refluxed for 3 h. The reaction mixture was cooled and poured into a flask containing 50 mL ethyl acetate and 50 mL 2N HCl. Stirred vigorously to hydrolyze the imine, separated the organic layer and dried it over anhydrous magnesium sulfate. The desiccant was filtered off and the solvent volume reduced under reduced pressure. The crude product was flash chromatographed on silica gel (92/8 hexanes/ethyl acetate) to give product. 1H NMR 500 MHz (CDCl3): δ 4.40 (s, 2H), 7.2-7.6 (m, 7H).

1. customthe supernatant was cannulated under nitrogen into another round bottom flask
2. customfitted with a magnetic stirrer bar
3. stirringthe mixture was stirred over night at room temperature
4. customThe imine precipitated out of solution
5. temperaturethe mixture was refluxed for 3 h
6. temperatureThe reaction mixture was cooled
7. additionpoured into a flask
8. additioncontaining 50 mL ethyl acetate and 50 mL 2N HCl
9. stirringStirred vigorously
10. customseparated the organic layer
11. dry with materialdried it over anhydrous magnesium sulfate
12. filtrationThe desiccant was filtered off
13. customchromatographed on silica gel (92/8 hexanes/ethyl acetate)
14. customto give product