Dichloromethane → Diisopropyl Ether

Participants

Reaction Steps

A cooled (0° C.) solution of 2-[(tert-butoxycarbonyl)amino]-1-[(4-cyanophenoxy)methyl]ethyl methanesulfonate (from step (iv) above; 30.6 g, 82.6 mmol) and tetrabutylammonium hydrogensulfate (3 g, 8.8 mmol) in DCM (100 mL) was treated with 50 wt. % aqueous NaOH (60 mL) under an inert atmosphere. The resulting mixture was stirred, and the temperature was slowly allowed to rise to rt over for 4 h, and then extracted with ether. The organic layer was washed with water and concentrated in vacuo to give a residue that was purified by column chromatography (dichloromethane eluent). Crystallisation from diethyl ether:di-iso-propyl ether gave the sub-title compound in quantitative yield.

Provenance & Evidence