EtOnArrow-pushing InstructionsEtO.OEtEtO:H3C>XTOEt1. NaOEt, EtOH2. H3O+In the mixed Claisen condensation, the donor and target molecules are different. The target molecule is chosen as one thatdoes not contain an acidic a-carbon. The donor molecule, as in the case of the standard Claisen condensation, is one that hasmore than one acidic a-hydrogen. The mechanism for the mixed Claisen condensation proceeds as for the standard reaction:nucleophilic attack of the enolate anion on the carbonyl group of the target, expulsion of the weakest base, deprotonation todrive the equilibrium forward, and subsequent protonation to give the final product.Draw curved arrows to show the movement of electrons in this step of the mechanism.EtO.the fileOEtOEtH HHEtO.OOEt+EtOHEtOH OEt00H3CH3CH3CEsters, like aldehydes and ketones, are weakly acidic. Treatment of an ester with 1 equivalent of a strong base, such assodium ethoxide, causes a reversible carbonyl condensation to occur that forms a ß-ketoester. This reaction is known as theClaisen condensation.XMwolpheH3CHOEtOEt1. NaOEt, EtOH2. H3O+The tetrahedral intermediate thus formed expels an alkoxide leaving group to give an acyl substitution product, a ß-ketoester. The steps leading up to this point are all reversible. The best yields for the Claisen condensation are obtainedwhen the starting ester has more than one acidic a-hydrogen. In these cases, a second deprotonation of the a-carbon drivesthe reaction equilibrium toward the product, thus requiring a full equivalent of base instead of a catalytic amount.Subsequent protonation with dilute aqueous acid results in high yield of the final product.Draw curved arrows to show the movement of electrons in this step of the mechanism.Arrow-pushing Instructions+H-OH₂O:H3CΗ ΗOEt+OEtEtOHH₂O

We have been given two reactions and we have been asked to draw curved arrows in mechanism. Organic…

EtO. NA EtO. C OEt XT U U H3C OEt OEt In the mixed Claisen condensation, the donor and target molecules are different. The target molecule is chosen as one that does not contain an acidic a-carbon. The donor molecule, as in the case of the standard Claisen condensation, is one that has more than one acidic a-hydrogen. The mechanism for the mixed Claisen condensation proceeds as for the standard reaction: nucleophilic attack of the enolate anion on the carbonyl group of the target, expulsion of the weakest base, deprotonation to drive the equilibrium forward, and subsequent protonation to give the final product. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions 1. NaOEt, EtOH 2. H3O* EtO. EtO. C OEt OEt EtOH EtOH

EtO. NA EtO. C OEt XT U U H3C OEt OEt In the mixed Claisen condensation, the donor and target molecules are different. The target molecule is chosen as one that does not contain an acidic a-carbon. The donor molecule, as in the case of the standard Claisen condensation, is one that has more than one acidic a-hydrogen. The mechanism for the mixed Claisen condensation proceeds as for the standard reaction: nucleophilic attack of the enolate anion on the carbonyl group of the target, expulsion of the weakest base, deprotonation to drive the equilibrium forward, and subsequent protonation to give the final product. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions 1. NaOEt, EtOH 2. H3O* EtO. EtO. C OEt OEt EtOH EtOH

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter4: Acids And Bases

Section: Chapter Questions

Problem 4.10P: Complete a net ionic equation for each proton-transfer reaction using curved arrows to show the flow...

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