反应详情

Add a solution of LiOH.H2O (1.83 g, 43.5 mmol) in water (30 mL) to a rapidly stirred solution of 5-[5-(2-methoxy-phenyl)-isoxazol-3-yl]-pentanoic acid ethyl ester (2.64 g, 8.7 mmol) in dioxane (60 mL) and stir overnight at room temperature. After 1 hour, acidify to pH 1 with 5N HCl solution and concentrate to remove the majority of the dioxane. Partition residue between 20% i-PrOH/CHCl3 and 1N HCl solution and separate layers. Backextract from aqueous layer with 20% i-PrOH/CHCl3 and dry combined organic layers over MgSO4, and concentrate to get 2.5 grams of a yellow oil. Recrystallize from EtOAc/hexanes to afford the title compound (1.96 g, 82%). MS (IS) 276 (M+1)+.

1. waitAfter 1 hour
2. concentrationconcentrate
3. customto remove the majority of the dioxane
4. customPartition residue between 20% i-PrOH/CHCl3 and 1N HCl solution and separate layers
5. dry with materialBackextract from aqueous layer with 20% i-PrOH/CHCl3 and dry
6. concentrationconcentrate