Tropinone

tropinone is an alkaloid, synthesised in 1917 by Robert Robinson as a synthetic precursor to atropine, a scarce commodity during World War I.

Related Topics:
Alkaloid - Robert Robinson - Synthetic - Atropine - World War I

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In organic chemistry the synthesis is considered a milestone in total synthesis. Tropinone is a complex bicyclic molecule but the reactants are fairly simple: succindialdehyde (see succinic acid and aldehydes), methyl amine and actone dicarboxylate (or even acetone). The synthesis is a good example of a biomimetic reaction or biogenetic-type synthesis because biosynthesis makes use of the same building blocks. It also demonstrates a tandem reaction is a one-pot synthesis.

Related Topics:
Organic chemistry - Total synthesis - Bicyclic molecule - Reactant - Succinic acid - Aldehyde - Methyl amine - Acetone - Biomimetic - Biosynthesis - Tandem reaction - One-pot synthesis

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The main features apparent from the reaction sequence below are:

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• step 1: Nucleophilic addition of secondary amine to aldehyde followed by loss of water to create an imine
• step 2: nucleophilic addition of the imine to the second aldehyde unit and first ring closure
• step 3: intermolecular mannich reaction of the enolate of actone dicarboxylate
• step 4: new enolate formation and new imine formation with loss of water for
• step 5: second intramolecular mannich reaction and second ring closure
• step 6: loss of 2 carboxylic groups to tropinone
 
Tropinone: references ►