Studies on the synthesis of 8-alkyl-8-aryl-2-azabicyclo[3.3.1]nonan-7-ones. A short synthetic route to functionalized 8-alkyl derivatives
摘要:
Two approaches to 8-alkyl-8-aryl-2-azabicyclo[3.3.1]nonan-7-ones are explored. They are based on the cyclization of an alpha-alkyl alpha-aryl ketone upon an iminium salt generated from 2-cyanopiperidine 13 and on the arylation of 8-alkyl-2-azabicyclo[3.3.1]nonan-7-one 20. An efficient, short synthetic route to 8-alkyl-2-azabicyclo[3.3.1]nonan-7-ones, using phosphonate 16 as a 5-functionalized 2-oxopentyl synthon, is reported.
An improved method for the synthesis of 4-azatricyclo [5.2.2.04,8] undecan-11-one (1) is reported. The synthesis involves hydrogenolysis of 8-hydroxyethyl-2-azabicyclo [3.3.1] nonan-7-one 3 followed by intramolecular alkylation of the resulting secondary amine 7. The required azabicyclic alcohol 3 was obtained by oxidative cyclization with mercuric acetate of the α-alkylated methyl 4-piperidineacetoacetate
Two approaches to 8-alkyl-8-aryl-2-azabicyclo[3.3.1]nonan-7-ones are explored. They are based on the cyclization of an alpha-alkyl alpha-aryl ketone upon an iminium salt generated from 2-cyanopiperidine 13 and on the arylation of 8-alkyl-2-azabicyclo[3.3.1]nonan-7-one 20. An efficient, short synthetic route to 8-alkyl-2-azabicyclo[3.3.1]nonan-7-ones, using phosphonate 16 as a 5-functionalized 2-oxopentyl synthon, is reported.