Question on stereogenic centers?

[treeclimbingmonkey]

Does anyone know why the answer is 1 stereogenic center?

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[Instance_Variable]

With adamantane derivatives, the groups attached have pretty rigid geometries. Because of that, the Cl, Br, CH3, and COOH groups in the molecule you posted are "stuck" in a fixed position pointing away from the ring structure at all times. This is due to steric strain and geometric limitations due to the ring. If you draw a line from each group to the center of the ring, you'll end up with something like this:

So, the molecule has one stereogenic center, but it is not located on a carbon atom; rather, it is in the center of the ring. Thus, this molecule has one enantiomer.

 

[treeclimbingmonkey]

With adamantane derivatives, the groups attached have pretty rigid geometries. Because of that, the Cl, Br, CH3, and COOH groups in the molecule you posted are "stuck" in a fixed position pointing away from the ring structure at all times. This is due to steric strain and geometric limitations due to the ring. If you draw a line from each group to the center of the ring, you'll end up with something like this:
View attachment 308848
So, the molecule has one stereogenic center, but it is not located on a carbon atom; rather, it is in the center of the ring. Thus, this molecule has one enantiomer.

Isn't a sterogenic center the same thing as a stereocenter, if so the carbons connecting to the hydrogen, fluorine, chlorine, and bromine are all stereocenters right?

 

[Instance_Variable]

The carbons connecting to the other groups are not stereocenters because the Br, Cl, CH3, and COOH are in a fixed position pointing away from the ring. In other words, those groups can't be dashed or wedged, and you can't interchange any groups on those carbons to create a new stereoisomer. The substituted groups are stuck in a single position. The center of the ring is a stereogenic center because you can create an enantiomer (non-superimposable mirror image) by rotating the molecule around that point.

Stereocenter and stereogenic center mean the same thing.

 

[treeclimbingmonkey]

Ahhhh I see! Thank you so much for the clarification! It makes sense now.