Question

The compound shown below is the product of a Claisen condensation. Draw structural formulas for the reactants: ester and enolate ion. Assume all esters to be ethyl esters. • Do not include counter-ions, e.g., Na+,r, in your answer. • Draw the enolate ion in its carbanion form. • Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. • Separate multiple reactants using the + sign from the drop-down menu.

Answer 1

1. The given product of Claisen condensation is HJ Note that the indicated bond must be cleaved retrosynthetically to get the reactants. The part to the right of the retrosynthetic bond must be the corresponding to the enolate as it has only one O atom. The part to the left of the retrosynthetic bond must be corresponding to the reactant ester. Hence, we can draw the reactants as follows: HC Ha ester enolate in carbanion form) We can draw the arrow pushing mechanism from the reactants above as follows: | HC Con - OE product

Here there are two reactants, one enolate (to be drawn in carbanion form) and one ester as shown above.

2. The given product of Claisen condensation is Note that this will be a intra molecular Claisen ester condensation as the bond formation is taking place between two substituents in a ring system. Hence, the enolate and the ester are enolate part on the ring ester part on the ring The mechanism of the reaction can be shown as HC Product

Hence, there is only one reactant here and you have to draw the structure containing both the carbanion form of the enolate and the ester.