(1R,6R)-1-methyl-8-azaspiro[5.6]dodecan-7one

Abstract

The crystal structure of the title compound, C12H21NO, has been investigated to establish the absolute stereochemistry at position 1. The absolute stereochemistry at the quaternary centre at position 6 is established to be R using an asymmetric Birch reductive alkylation reaction for which the stereochemical outcome is known. The crystal structure indicates the presence of two conformers of the bicyclic (1R,6R)-spirolactam ring system that differ in the conformation adopted by the six-membered ring. In one conformer, the methyl group adopts an axial position whereas in the other conformer, the same methyl group adopts an equatorial position. In both conformers, the seven-membered ring adopts a chair conformation. The two conformers of the bicyclic spirolactam are connected to each other via intermolecular N-HO hydrogen bonds forming a heterodimer. The asymmetric unit contains two such dimers.