Hydrochloric Acid → 5,8-difluoro-4-methyl-3,4-dihydro-1(2H)-naphthalenone

Temperature

110 °C

1,4-Difluorobenzene (22 ml, 210 mmol) was mixed with gamma-valerolactone (4 ml, 42 mmol) and AlCl3 (28 g, 210 mmol) was added by portions to the stirred reaction mixture. The reaction mixture was then refluxed at stirring for 16 h (oil bath 110° C.). The reaction mixture was cooled down (ice/brine bath) and ice/conc. HCl was added and stirred until homogeneous mixture was obtained. The reaction mixture was then extracted into methylene chloride, washed with water (4×10 ml) and sodium bicarbonate solution (3×100 ml). The organic extract was dried over Na2SO4. Concentration by rotary evaporation gave 6.7 g of product as yellow powder. Yield 81%.

1. additionwas added by portions to the stirred reaction mixture
2. temperatureThe reaction mixture was then refluxed
3. stirringstirred until homogeneous mixture
4. customwas obtained
5. extractionThe reaction mixture was then extracted into methylene chloride
6. washwashed with water (4×10 ml) and sodium bicarbonate solution (3×100 ml)
7. extractionThe organic extract
8. dry with materialwas dried over Na2SO4
9. concentrationConcentration
10. customby rotary evaporation

ORD record

ord-8e64bca61d944fdfba52bb9d9a959cd2

Source dataset

uspto-grants-2009_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07517992B2