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I have to assign R or S to the chiral centers in (-)-menthol and (+)-neomenthol.

The results I got are shown below in the picture.

enter image description here

However, when I looked on Wikipedia to check my answers they said the answers were for (-)-menthol [1R, 2S, 5R] and for (+)-neomenthol [1S, 2S, 5R].

I thought the stereocenter had to be chiral and have four different groups off the carbon in order to assign it R or S, why does each molecule have 8 stereocentres when I think there are only three.

Another question it asks is what is the relationship of the two compounds?

I'm fairly certain they are diastereomers. Is this correct?

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    $\begingroup$ You misinterpreted what [1R, 2S, 5R] means. It states that the 1 position has the R configuration, the 2 position is S and the 5 position is R. $\endgroup$ – LDC3 Oct 12 '14 at 0:11
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    $\begingroup$ @LDC3 In order to close this question, would you consider leaving this as an answer? I think there is hardly any more to say. $\endgroup$ – Martin - マーチン May 10 '15 at 10:08
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[1R, 2S, 5R] means that the 1 position has the R configuration, the 2 position is S and the 5 position is R. When a ring has at least 2 substitutes, then the carbons with the substitutes could also be a chiral center.

There are only 3 chiral centers, but there are 8 stereoisomers.

Yes, they are diasteriomers.

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