Absolute configuration help

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circulus vitios

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I'm 'relearning' (learning) absolute configuration and I still suck at it.

12diclc6.gif

For the trans molecule, I understand why the top stereocenter is R. The hydrogen is already facing away. Priority in decreasing order is: chlorine, CClH, CH2, and that's clockwise so it's R.

The bottom stereocenter I don't get. H is facing toward me so couldn't I just switch Cl and H to give me this (pardon my crap mspaint skills):

12diclc6.gif


Priority in decreasing order is: chlorine, CClH, CH2, which is counterclockwise or S...but it says R! What am I doing wrong?
 
Never mind, I forgot that switching two groups changes the direction. So it is S, but it gets switched to R. :uhno: I hate organic chemistry so much.
 
High five to you for posting your own explanation rather than just deleting the whole post...it's totally dumb on my part but I get irritated every time I browse through here, and when I open a thread it consists entirely of "NM LOL I figured it out"

I know, it wasted what, like 3 seconds of my life? But anyway, good on you for how you did it. 🙂
 
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