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I'm trying to find the R/S configuration of this molecule right here: Molecule structure

At first I tried to find the rotation and then reverse it (since H is pointing outwards), I got an S configuration (drawn poorly here):

First attempt

Then I tried to use the enantiomers method. I swapped the Br and the H then tried to find the configuration of the new molecule. And, I got an S configuration (of the resulting new molecule, which leads to the original having R configuration), which is not what I expected:

Second attempt

I don't know what I've done wrong here, the two attempts should lead to the same result (unless I've done something wrong). I tried looking up other R/S config examples using the enantiomers method (switching method) and what I've noticed is that the wedge and the dotted lines are right next to each other, like this for example:

enter image description here

While the molecule above has a straight (?) line in between:

enter image description here

So does that mean I can only switch groups when the wedge and the dotted lines are next to each other? Or was the first method wrong? Please kindly explain. Thank you.

Update 1 I've added a 3D visualization of the molecule. The big red ball is bromine, the gray medium-sized balls are carbon atoms, and the little white ones are hydrogens. I've marked the chiral center (green arrow pointing to it) for clarity. I've also rotated the molecule so that the bromine is pointing outwards.

Model

RandomizedM
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    Have you tried building a 3D model to make sure you have not mistakenly swapped the configuration? – matt_black Oct 06 '22 at 12:49
  • @matt_black I've looked at the ball and stick model of the molecule (on KingDraw), then I tried switching the Br and H around. From what I observed, the molecule seems to have R configuration. I'll leave an image of the molecule on the question asap. – RandomizedM Oct 06 '22 at 12:57
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    Just my two cents: the way your stereocenter is drawn seems to make it unassignable (it is ambiguous). With that perspective, you could have either two wedged bonds or two dashed bonds to form a tetrahedron. Both your assignments are correct but for different (and unattainable) carbon geometries. The angles are a mess. – TheRelentlessNucleophile Oct 06 '22 at 13:47
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    I agree, poor drawing! Make the carbon in question look like it is tetrahedral. In your first picture, move the dashed bromine pointing northeast to a position pointing northwest, and still dashed ,just above the bold hydrogen. Now you should have no problems in visualization. – user55119 Oct 06 '22 at 19:53
  • @TheRelentlessNucleophile Thanks for pointing that out! Yeah the stereocenter does look kinda weird now that I've looked at it. It's more like two lines intersecting than a tetrahedron. I was just curious to see how this molecule would have its configuration assigned (the problem was to draw (2S,3E)-2-bromohept-3-ene, and that was the molecule my prof. drew). – RandomizedM Oct 07 '22 at 05:49
  • @user55119 So I can freely move the bromine that's pointing inwards (dashed lines) without changing the configuration right? Like this one for example. – RandomizedM Oct 07 '22 at 05:49
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    As long as it keeps pointing inwards, yes. – Ivan Neretin Oct 07 '22 at 06:55
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    Follow Ivan's lead. I would tweek tha methyl group like this. You might be interested in this. – user55119 Oct 07 '22 at 18:57

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