Hi, I'm an undergraduate student and I am right now struggling with organic synthesis. In particular, I need to know the products of this reaction for laboratory work in a few weeks, when the pandemic is over. Thank you in advance.
I agree with the above product A, B, C , D and E. You are mentioning i ma studying in under graduate. But when you are handling KCN you should very careful and quench properly underacted KCN and all the utilized things in the reaction after completion of reaction.
I agree with Ramin Javahershenas in that the disposal of unreacted KCN should be done with great care. Any contact with acid would produce highly toxic HCN. The KCN is best destroyed with sodium hypochlorite (NaOCl) or H2O2 in an alkaline medium.
Just in case you want to find out more:
A: formed by Knoevenagel condensation
A->B: Michael addition and Krapcho decarboxylation
B->C: acidic hydrolysis of the nitrile and ester function
C->D: anhydride formation
D->E: Friedel Crafts acylation
In my humble opinion, the structure of the final product is different (see attached). It all depends on the conditions for step B => C. And, by the way, B to C is not a Krapcho decarboxylation ...
Dr. Haak's answer is certainly correct if we assume that nitrile is hydrolyzed to carboxylic acid on B => C step; however, in my opinion the conditions for this step are not defined sufficiently to exclude other possibilities. What if only ester groups are hydrolyzed and nitrile remains intact? Or if nitrile is partially hydrolyzed to amide?
It is well known that nitriles are much more resistant to hydrolysis than esters. Chances are that the intermediate malonic acid derivative will decarboxylate before nitrile is hydrolyzed, giving beta-cyano acid C, which at the end will be cyclized to cyano-indanone (see attached scheme).
Your comments are welcome.
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