Cornforth reagent → 1-(5-Bromo-2-chlorophenyl)ethan-1-one

Pyridinium dichromate (2.6 g, 6.94 mmol) was added to a solution of 1-(5-bromo-2-chloro-phenyl)-ethanol (1.09 g, 4.6 mmol) in CH2Cl2 (20 mL). The reaction was stirred for 15 hours and then more pyridinium dichromate (2.6 g, 6.94 mmol) was added. After another 24 hours celite was added and the mixture was stirred for 20 mins. The reaction mixture was filtered through a pad of celite washing with ether. The filtrate was concentrated to a brown oil. The residue was purified by flash silica gel chromatography (0% to 10% EtOAc in hexanes) to give the title compound as a clear oil (0.92 g, 85%). 1H NMR (400 MHz, CDCl3): δ 2.64 (s, 3H), 7.29 (d, J=8.6 Hz, 1H), 7.51 (dd, J=8.6, 2.3 Hz, 1H), 7.66 (d, J=2.3 Hz, 1H).

1. additionAfter another 24 hours celite was added
2. stirringthe mixture was stirred for 20 mins
3. filtrationThe reaction mixture was filtered through a pad of celite
4. washwashing with ether
5. concentrationThe filtrate was concentrated to a brown oil
6. customThe residue was purified by flash silica gel chromatography (0% to 10% EtOAc in hexanes)

ORD record

ord-82bbd7acc51948138bc8156dcf06567f

Source dataset

uspto-grants-2009_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07473790B2