Crystal structure of the meta hydroxyl phenyl analog of α(+)-prodine

The meta hydroxyphenyl analog of α-prodine (1,3-dimethyl-(4-meta-hydroxy phenyl)-4-propionyloxypiperidine) free base crystallizes in the orthorhombic space group P212121. The relative configuration of the compound shows the piperidine ring is in a chair conformation, the phenyl ring, the 3-methyl, and the N-methyl are equatorial, and the 4-propionyloxy group is axial. The molecular structure is similar to that of racemic α-prodine and the potent opioid agonist, ketobemidone. There is a hydrogen bond between N(1) ... O(1) 2.79 A.