Simple Absolute Configuration Question?

[SiakTiDoc]

Hi everyone I had a quick question about absolute R/S Configuration dealing with SN2 backside attack.
So, I'm aware that the configuration inverts when an SN2 undergoes backside addition (S => R)

If one of the groups that is inverted was an H on a dash that is now on a Wedge, do you still use the same configuration? After inversion (In this case R?) Or do you rotate it so that the H is on a dash (behind) and thus change the configuration again? Like in fishcer diagrams?
From S to R back to S?

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[aldol16]

Configuration should not change if you're just rotating the molecule. It doesn't matter at all how you draw the product. As long as the absolute configuration is correct at the end, that's all that matters.

 

[SiakTiDoc]

Configuration should not change if you're just rotating the molecule. It doesn't matter at all how you draw the product. As long as the absolute configuration is correct at the end, that's all that matters.

So if something is S config. undergoes => SN2 Backside => R Config.
It stays that way even if the Hydrogen is now on a wedge instead of a dash like previously?

 

[aldol16]

So if something is S config. undergoes => SN2 Backside => R Config.
It stays that way even if the Hydrogen is now on a wedge instead of a dash like previously?

If something is S and undergoes SN2 attack, then it becomes R. No matter how you draw it, it must be R. There are various ways to draw an R enantiomer but as long as it's R, you're good.

 

[DelayedGratification]

the wedge is what is signifying the inversion of configuration if you think about

when you rotate the molecule to put the H back in the rear(dash), the groups on the left and right will be swapped

 

[aldol16]

Look past the way you draw things - that's just convention to represent 3D molecules on 2D paper. Think about what you're drawing and try to actually "see" the dashes going into the page and the wedge coming out. Then it should be evident to you how inversion occurs.

 

[SiakTiDoc]

Thank you both for the help!