Acyl Derivatives: Multi-Step Synthesis
Suggest a synthetic scheme for the conversion shown on the left using the starting material indicated. Work each problem backwards, and draw the structures of the intermediate required for the conversion, and the reaction conditions necessary for each step.Click the mouse on the buttons to view the synthetic logic, the structure of the intermediate and the solution to the problem.
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Working backwards, a saturated carbon and a primary amine have been added to the carbon skeleton of the starting material; further, the carbonyl group has been reduced to an alcohol. The CH2NH2 group can be formed by the reduction of an amide or a nitrile. Since the starting material is an a-b-unsaturated ketone, a nitrile group could be easily introduced at the b-position using diethylaluminum nitrile; the nitrile and the carbonyl could then both be reduced with LiAlH4. First, draw the structure of the intermediate nitrile and the conditions necessary for the reduction.
A saturated carbon and a primary amine have been added to the carbon skeleton of the starting material; further, the carbonyl group has been reduced to an alcohol. The CH2NH2 group can be formed by the reduction of an amide or a nitrile. Since the starting material is an a-b-unsaturated ketone, a nitrile group could be easily introduced at the b-position using diethylaluminum nitrile; the nitrile and the carbonyl could then both be reduced with LiAlH4, as shown above. Next, give the conditions necessary for the conversion of 3-buten-2-one to the intermediate nitrile.
3-Buten-2-one is reacted with diethylaluminum nitrile reagent to give 4-oxopentanenitrile. The nitrile and the carbonyl are then both be reduced with LiAlH4 to give the final product.