Many alkaloids appear to be synthesized in plants by reactions that resemble the Mannich reaction. Recognition of this (by R. Robinson in 1917) led to a synthesis of tropinone that takes place under “physiological conditions,” that is, at room temperature and at pH values near neutrality. This synthesis is shown here. Propose reasonable mechanisms that account for the overall course of the reaction.

Transcribed Image Text:

О Н H + CHINH, + CO_H CO H H₂O 25 °C -CH₂ Tropinone + 2 CO2