I'm studying organic chemistry, more specifically the imines and enamines. I've read about the mechanism of formation of enamine from a generic ketone and a question popped up in my mind. The mechanism proposed by my book (and everywhere else) goes from the ketone, to the iminium ion when the water molecule goes out, and then to the enamine by the the breaking of the C=N double bond. Now, I've studied in the past the reactions of alcohols, and I remembered that a tertiary alchol can undergo by dehydration as an elimination reaction (E1 or E2), forming as a consequence a C=C bond. Now going back to the enamine formation where the water molecule is present, can't the water go out with the direct formation of the C=C bond forming the enamine by conseguence? Is the choice of the mechanism determinated by some kind of kinetics or spectroscopic study that confirm the presence of the iminium ion?

  • $\begingroup$ During enamine formation, “water does not go out” but rather hydroxide does. The hydroxide deprotonates the immonium cation to form water and the enamine. The immonium cation is isoelectronic with a ketone, and it is more readily deprotonated. $\endgroup$
    – user55119
    May 26, 2023 at 14:01


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.