1,8-Diazabicyclo(5.4.0)undec-7-ene → 3-(3,4-Difluorophenoxy)-5,5-dimethyl-4-(4-(methylsulfonyl)phenyl)-5H-furan-2-one

Participants

Reaction Steps

A solution of 3,4-difluorophenoxyacetic acid (0.51 g, 2.73 mmol), 2-hydroxy-2-methyl-1-(4-(methylsulfonyl)phenyl)propan-1-one (0.5 g, 2.1 mmol, Step 3), CMC (1.13 g, 2.73 mmol) and DMAP (15 mg, 0.10 mmol) in dichloromethane (12 ml) was stirred at r.t. for 18 hrs. Then, DBU (0.63 ml, 4.2 mmol) was added and the reaction mixture was refluxed for 3 h. After cooling to r.t. the mixture was extracted with ethyl acetate and washed successively with water, 1N HCl and brine. The organic layer was dried over MgSO4, filtered and the solvent evaporated under vacuum. The residue was triturated in a mixture of ethyl acetate and hexane affording the title compound as a solid. M.P.: 93-95° C.

Provenance & Evidence