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Stereocenters

Started by NA19
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NA19

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Is the last stereocenter (the one on the very right) R or S?
 

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R I think because the H is coming out of the page


This was actually something that I was planning on looking up to double check

someone clarify for me if i'm wrong
 
But it doesn't even show the H? I thought it would be S because priority #1 is the OCH2CH3 group, priority #2 is the C with the OH attached, and then priority #2 is the CH3 group. So it goes counter clockwise.
 
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But it doesn't even show the H? I thought it would be S because priority #1 is the OCH2CH3 group, priority #2 is the C with the OH attached, and then priority #2 is the CH3 group. So it goes counter clockwise.

Doesn't need to show the H, we know it's there. It would be S, but since the H isn't going going into the page (by convention), then it is R.
 
So if the H isn't shown, do you assume it's coming out of the page?
That depends; usually the main carbon chain is in the plane of the page and substituents are sticking in/out of the plane. If a substituent is pointing forwards with a wedge bond, you assume the hydrogen is backwards with a dashed bond, and vice versa. So it all depends on the depiction of the more important group.