Potassium Iodide → HCID 86755139, compound

Participants

Reaction Steps

To a solution of (+)-(5S)-1-(4,5-diphenyloxazol-2-yl)-5-(3-methoxybenzyl)cyclopentene (2.33 g) in methylene chloride (10 ml), was added boron tribromide in methylene chloride (1M, 9 ml) at 0C. After 3.5 hours stirring at the same temperature, the reaction mixture was washed with water and saturated aqueous sodium hydrogencarbonate. Drying (sodium sulfate) and removal of solvent afforded a yellow syrup containing (+)-(5S)-1-(4,5-diphenyloxazol-2-yl)-5-(3-hydroxybenzyl)cyclopentene. An acetonitrile solution (20 ml) of the yellow syrup, potassium carbonate (1.30 g), methyl bromoacetate (0.98 g) and potassium iodide (a catalytic amount) was stirred under reflux for 3.5 hours. The solvent was evaporated in vacuo and the residue was partitioned between ethyl acetate and 1N hydrochloric acid. The organic layer was washed with 1N hydrochloric acid, water and brine. Drying (sodium sulfate) and removal of solvent at reduced pressure followed by flash chromatography over 50 g of silica afforded (+)-methyl [3-[[(1S)-2-(4,5-diphenyloxazol-2-yl)-2-cyclopenten-1-yl]methyl]phenoxy]acetate (2.10 g, 98.2% ee) as a yellow oil.

Provenance & Evidence