Dimethylformamide → 4-Fluoro-2-methylbenzaldehyde

A -78° C. solution of 2-fluoro-5-bromotoluene (25.764 gm, 136.3 mmol) in THF (200 ml) was treated with n-BuLi (2.5M in hexane, 60 ml, 150 mmol) over a 12-minute period. After stirring for one hour, the cloudy white mixture was treated with neat dimethylformamide (30 ml, 28.3 gm, 387 mmol) over a two-minute period. Stirring continued for an additional hour. The mixture was then quenched with saturated NH4Cl, warmed to room temperature, and made acidic with 10% HCl. The mixture was extracted with Et2O and the ether extract was washed with H2O and brine, then dried (Na2SO4), filtered, and stripped. The dark residue was distilled (bp 55° C. @1 mm) to give the title compound (16.286 gm, 86%).

1. stirringStirring
2. waitcontinued for an additional hour
3. customThe mixture was then quenched with saturated NH4Cl
4. extractionThe mixture was extracted with Et2O
5. extractionthe ether extract
6. washwas washed with H2O and brine
7. dry with materialdried (Na2SO4)
8. filtrationfiltered
9. distillationThe dark residue was distilled (bp 55° C. @1 mm)

ORD record

ord-1b48b42f01d84375a69fe27aa3fcd0ef

Source dataset

uspto-grants-1997_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05691322