Boron tribromide → 3-{5-[3-(2-Hydroxy-ethoxy)-phenyl]-pyridin-2-yloxy}-azetidine-1-carboxylic acid pyridazin-3-ylamide

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Reaction Conditions

Reaction Steps

3-{5-[3-(2-Benzyloxy-ethoxy)-phenyl]-pyridin-2-yloxy}-azetidine-1-carboxylic acid pyridazin-3-ylamide (Example 9, 325 mg, 0.65 mmol) was dissolved in anhydrous dichloromethane (10 mL) under a nitrogen atmosphere. The mixture was cooled with an ice water bath and boron tribromide in dichloromethane solution (1M, 0.98 mL, 0.98 mmol) was added drop-wise affording a precipitate. The reaction mixture was stirred at 0° C. for 2 hr. The precipitate was collected by filtration and purified by flash chromatography on silica gel eluting with ethyl acetate, then 5-10% methanol in DCM. Further purification by preparative HPLC at pH4 afforded title compound (13 mg, 5%) as colourless solid.

Provenance & Evidence