Beilstein J. Org. Chem.2012,8, 1877–1883, doi:10.3762/bjoc.8.216
relative configurations of tert-butyldimethylsilyl (TBDMS) ethers of all four diastereomers of the aldols of tropinone (8-methyl-8-azabicyclo[3.2.1]octan-3-one), as well as of granatanone (9-methyl-9-azabicyclo[3.3.1]nonan-3-one), were determined from NMR data, and from the observed interconversion of the
isomerization; granatanone; stereoselective reaction; tropinone; Introduction
Enantiomerically pure, and racemic, diastereomerically pure aldols of tropinone have been used as key intermediates in stereoselective syntheses of natural tropane alkaloids and their analogues [1], including the unnatural enantiomer
and enantiomerically pure aldols of tropinone (8-methyl-8-azabicyclo[3.2.1]octan-3-one) and granatanone (9-methyl-9-azabicyclo[3.3.1]nonan-3-one) (Figure 1) were synthesized by enantioselective deprotonation with lithium amide bases followed by diastereoselective aldol reaction with aldehydes [10][11
PDF
Graphical Abstract
Figure 1:
The exo and the endo substituents at the α-carbon (C-2 by tropane numbering) of the tropinone or gr...