ASYMMETRIC SYNTHESES OF THE LADYBUG ALKALOID ADALINE AND 1-METHYL-9-AZABICYCLO (3.3.1)NONAN-3-ONE

Article abstract of DOI:10.1016/0040-4020(82)80045-8

The double Michael addition of benzylamine to 3-alkyl-2,7-cyclooctadienones, followed by hydrogenolysis, affords bridgehead substituted 9-azabicyclo(3.3.1)nonan-3-ones.Use of (+)-α-methylbenzylamine in the addition leads to mixtures of diastereometric adducts in unequal amounts.Although the degree of asymmetric induction is low (10-20 percent ee), the diastereomers can be easily separated, affording pure enantiomeric forms of the ladybug alkaloid adaline 1 and the Euphorbia alkaloid 3.