Structure of 2-(α-hydroxybenzyl)-8-methyl-8-azabicyclo[3.2.1]octan-3-one

The unambiguous structure of the title compound (which was formed in the reaction of the lithium enolate of tropinone with benzaldehyde) has been determined to be the exo-anti diastereoisomer. The piperidine ring adopts a flattened-chair conformation with the carbonyl group pushed away from the ethylene bridge. There is an intermolecular hydrogen bond between the hydroxyl group and the N atom which replaces the intramolecular O-H...N hydrogen bond indicated by solution NMR data