Hydrochloric Acid → T-817 maleate

Participants

Reaction Steps

To tetrahydrofuran (5 mL) suspension of 1.00 g of 1-(3-(2-(1-benzothiophen-5-yl)ethoxy)propionyl)azetidin-3-ol was added 0.37 g of sodium borohydride, and dropwise added tetrahydrofuran (1 mL) solution of 0.75 mL of trifluoroacetic acid for 30 minutes, which was then refluxed for 2 hours. After cooling, thereto was dropwise added 3.27 mL of 6.0 mol/L hydrochloric acid, which was then refluxed for 1.5 hours. To the reaction mixture were added water and ethyl acetate, and the aqueous layer was separated. To the aqueous layer was added ethyl acetate, and the pH was adjusted to 10.0 with 20% (w/w) sodium hydroxide aqueous solution. The organic layer was separated, washed sequentially with water and saturated sodium chloride aqueous solution, and dried over anhydrous magnesium sulfate. After insoluble matter was filtered off, the solvent was distilled off under reduced pressure. To the resultant residue was added 0.36 g of maleic acid, which was solidified from a mixed solvent (5 mL) of ethyl acetate:2-propanol (4:1) to provide 0.62 g of 1-(3-(2-(1-benzothiophen-5-yl)ethoxy)propyl)azetidin-3-ol maleate as colorless crystal form.

Provenance & Evidence