Oxalyl chloride → 3-Fluoro-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-one

Participants

Reaction Steps

A mixture of 2-[2-(4-fluorophenyl)ethyl]benzoic acid (4.00 g, 16.4 mmol, 1 equiv) and oxalyl chloride (2.0 mL, 2.9 g, 23 mmol, 1.4 equiv) in CH2Cl2 (50 mL) was refluxed for 30 min. The resulting solution was then added to a stirring suspension of aluminum chloride (3.0 g, 2.2 mmol, 1.4 equiv) in CH2Cl2 (50 mL). This mixture was refluxed for 1 h. The reaction mixture was then washed with 1N HCl (3×50 mL), aq. satd. NaCl (1×50 mL), and H2O (1×50 mL). The organic layer was dried (anh. Na2SO4) and rotary evaporated (75° C.) to provide 3.7 g of a dark-brown oil. This oil was flash chromatographed (20:1 hexane/EtOAc) through flash silica gel (250 mm×25 mm). Evaporation of the combined fractions of interest provided 1.58 g (42.6%) of the desired product as a yellow oil.

Provenance & Evidence