Bicyclic dimethylarylamine opioids - I need more for training set. Help please?

[S.J.B.]

that's news to me. Like all other 1,4 substituted cyclohexanes BDPC is a chiral compound with 2 chiral centres and 4 possible configurations (+)/(-)-cis/trans. You can have both the hydroxy and the amine equatorial (one trans isomer), the hydroxy equatorial and the amine axial (one cis isomer), the hydroxy axial and the amine equatorial, (another cis isomer), or both hydroxy and amine axial (another trans isomer).

4 images of each isomer for your viewing pleasure:

The first two images are of the same compound, with one being the ring-flip of the other. Same with the third and fourth images, although there has also been a 180 degree rotation of the molecule. You have shown, therefore, two diastereomers and two conformations of each diastereomer. There are no enantiomers.

 

[sekio]

dur, I forgot about cyclohexane chair inversions. So there's only a cis and trans isomer

 

[clubcard]

The trans axial & equatorial are conformers rather than isomers, are they not? I admit I had not considered the energy barrier as I should have.

 

[S.J.B.]

The trans axial & equatorial are conformers rather than isomers, are they not? I admit I had not considered the energy barrier as I should have.

Indeed, they are conformers, and the barrier to inversion in simple cyclohexanes like this is generally low enough that it occurs rapidly at room temperature in solution. For both the cis and trans isomers, I would imagine that the molecule will be mostly in the conformation that puts the phenethyl group equatorial, assuming the molecule is protonated, as the phenyl and alkyldimethylammonium groups should have roughly the same propensity to be equatorial whereas the phenethyl group will be preferred by about 1 kcal/mol over the hydroxyl (see this table of A values, a measure of the propensity of groups to be equatorial vs. axial).