Question

СО cat. H + NH2CH3 + H2CO2C CO2CH3 CO CHE Cocaine has been prepared by a sequence beginning with a Mannich reaction between dimethyl acetonedicarboxylate, methylamine, and butanedial. The mechanism involves the following steps: 1. Following initial protonation of the carbonyl oxygen, nucleophilic attack by the amine forms carbinolamine 1; 2. Proton transfer and elimination of water forms iminium ion 2; he enol form of the dicarboxylate ester attacks the iminium ion to form adduct 3; 4. Adduct 3 tautomerizes to form enol 4; 5. Following protonation of the aldehyde, cyclization occurs as protonated carbinolamine 5 is formed; 6. Proton transfer and elimination of water lead to iminium ion 6; 7. The enol attacks the iminium ion in a second cyclization reaction to form bicyclic ion 7; 8. Deprotonation leads to the final product. 1 pt Write out the mechanism on a separate sheet of paper and then draw the structure of bicyclic ion 7 1 pl 1 p • You do not have to consider stereochemistry,

Answer 1

HH 84H HN-CH N = Cih IN- Me -Corme MN coane M, T .com Come IH come "Cozme addwr H han me CN me hume wane cozine cozme Lozme Hol come U TOH Oh come Coome Boome loome come Hom cozme Final & product

He Hot Lp N OHH O permende COM i h® Hos final product- ELOH Eton aldol product e xetnar structure of oxyanions