Hydrochloric Acid → HCID 20511955, compound

Participants

Reaction Steps

To a solution of 34 (33.06 g, 206 mmol) in methylene chloride (580 mL) was added 80% m chloroperbenzoic acid (52.0 g, 211 mmol) and the mixture heated at reflux for 17 hours. The reaction mixture was allowed to cool, diluted with ethyl acetate (580 mL) and extracted with 5% NaHCO3 (2×725 mL). The aqueous layers were back extracted with additional portions of ethyl acetate (290 mL) and the combined organic layers dried (MgSO4) and concentrated. The resulting yellow oil (47 ) was taken up in methanol (700 mL) and 2.5N NaOH (185 mL, 462 mmol) was added. The mixture was stirred at room temperature for 20 minutes, cooled with an ice bath, and acidified with 2N HCl (810 mL). The resulting mixture was saturated with NaCl and extracted with ethyl acetate (3×1200 mL). The combined extracts were washed with 20% NaCl (2×900 mL), dried (MgSO 4) and concentrated. The resulting dark oil (51 g) was chromatographed through a large (9 cm diameter) column of flash silica gel. Elution with 12.5% ethyl acetate in hexane afforded 36 as an off white solid.

Provenance & Evidence