Hydrochloric Acid → Hydrochloric Acid

Participants

Reaction Steps

Solid 1-fluoro-2-bromomethyl-3-phthalimidopropene (0.60 g) is added to a previously prepared mixture of isopropanol (0.12 g) and sodium hydride dispersion (96 mg of 55-60% oil dispersion) in dimethylformamide (10 ml) at room temperature. Stirring is continued for 3 hours, then brine is added and the product is isolated by ether extraction. This product is treated with hydrazine hydrate (0.13 g) in ethanol (20 ml) under reflux for 3 hours. Dilute aqueous hydrochloric acid is added and the resulting mixture is washed with ethyl acetate, then the aqueous layer is concentrated to about 5 ml. The residual solution is treated with di-tert-butyl dicarbonate (0.44 g), sodium chloride (1 g) and chloroform (20 ml) then sufficient sodium bicarbonate is added to adjust the pH of the aqueous layer to about 8. The mixture is refluxed for 11/2 hours then the crude N-Boc derivative can be isolated by extractive work-up. Purification is achieved by silica chromatography using ether/petroleum ether as eluent. Cleavage of the Boc protecting group (anhydrous hydrogen chloride in ether) affords (Z)-2-isopropoxymethyl-3-fluoroallylamine as its hydrochloride salt.

Provenance & Evidence