750 POINTS Can someone please and and explain this? Need a lot of help Joe wants

Question

750 POINTS Can someone please and and explain this? Need a lot of help

Joe wants to run the multistep organic transformation shown below but he's having problems: every time he tries to conduct the reaction, it completely fails and he simply isolates the starting ketone, 1, unchanged. We'll see many reactions like this in the future, but, for now, some translation is in order. This is a two-step reaction: in Step 1, the ketone 1 is treated with the strong base 2 (think of this as being analogous to the conjugate base of ammonia) in the solvent ethanol (HOCH2CH3, a very common organic solvent) to produce the intermediate 3 (this is the conjugate base of the original ketone 1). In Step 2, the alkylating agent 4 is added to the reaction mixture containing the intermediate anion 3 which then reacts (follow the curved arrows!) to give the final product 5 (this is a ketone, like 1, but with an additional carbon). Joe's synthetic plan includes a very fundamental acid-base error that means the reaction, as shown, will fail every time! Explain Joe's mistake.

Explanation / Answer

The solvent used for this reaction (ethaol) is having a hydroxyl proton which is more acidic than alpha protons of ketone and being solvent, it is present in large quantity than ketone. Thus, base will get used up in abstracting proton of ethanol and no reaction with ketone will take place. Thus, given reaction will fail every time. Such reactions should be carried out in non protic dry solvents such as THF, diethyl ether, dioxane, etc.

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