Reaction to the product stereochemistry

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ahazen
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I need help writing the reaction to the product.
I know the wedge and dash are R and S.

I am stuck on what to do...please help me

Thank you
 
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oops, sorry about that.
Here is the structure image
 

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You have two stereocenters there. Arrange them so that the hydrogens are dashed. Determine the priority order. Go from highest priority to lowest. Clockwise is R.

Your answer will be one of R,R; R,S; S,R; S,S.
 


Are you trying to determine the product of this reaction? It's going to be an E1 elimination. I'll explain how I figured that out:

-Potassium t-butoxide is a strong base and a weak nucleophile, so nucleophilic substitution will be unlikely (and that is a competitive reaction with eliminations). This leaves you with two options: E1 or E2 elimination.
-E2 elimination is unlikely in a polar solvent (t-butanol).
-The substrate molecule has an allylic bromine. If the C-Br bond were to spontaneously break, the carbocation formed would have resonance stabilization. As such, a mechanism involving a carbocation is likely, especially considering that the solvent is polar and can stabilize the carbocation even more.