# How to wedge d/hash notation a molecule?

This is probably trivia for many of you (I already feel the pressure by even posting this question). Yet funny enough, most of the time the materials I have come across show the wedge-d/hash notation. Then due its cumbersome or what not, the material decides to propose Fisher project as a better notation. But frankly that doesn't give the proper picture of the stereochemistry or least understanding of how the atoms would arrange in space.

When revising Rectus-Sinister (R/S) system for stereochemistry, it has almost always indicated about assigning priority to the groups by descending order of the atomic number and that lowest priority substituent should always point away from the plane of the central atom. Speaking of a simple molecule like $\ce{CH4}$, Wedge-Dash is ideally suited to show structure of sp3 hybridised (tetrahedral atoms).

But what about more complex compounds/molecules like amino acids or things like drugs like morphine etc? or even an imaginary molecule given in exam? I dread at the thought of it.

I went through this question for few days now, before posting this question. Perhaps it has more advanced perspective compared to the simplicity of my question I think.

So are there direct guidelines to draw the wedge-h/dash notation for a given complex molecule? Am I really missing something from preliminary general chemistry here?

Obviously there are online applets that allow to get a SMILE of a molecule and generate the 3D structure like JSmol. I also know there are complex methodologies employed in higher level of physical science to determine the structure of molecules. But at this beginning level, is there anyway to determine the 3D structure of a molecule? At least to get a feeling of it, and to predict that what atom/side chain would pop out of plane and remain in the plane?

and for each centre you may find a pair of either configuration; for example for the hydroxyl group in $\alpha$ position to carbonyl alone
In total (for 3 stereogenic centres), there are $2^3 = 8$ distinct stereoisomers possible with different properties, which all fit into the first "line only" general representation.