I prepared the Weinreb amide from (+)-isocampholenic acid, which I then converted into the corresponding epoxide using 3-chloroperoxybenzoic acid. In the next step, I attempted to open the epoxide on the less substituted side using potassium hydroxide. However, the reaction did not proceed only the Weinreb amide hydrolyzed. To overcome this problem, I replaced the amide side group with an ether group, which is more stable, and repeated the epoxidation and epoxide opening reactions, first under basic and then under acidic conditions.
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