What is/are the product(s) of the potassium permanganate reaction with (R)-4-methyl cyclohexene?

Question

Is the product a meso molecule, racemic mixture, or other mixture, and if so, what kind of mixture?

If the product is a mixture, do you expect the compounds to have the same or different physical properties? Would you expect to be able to separate them with TLC and column chromatography?

Answer 1

You have not stated the conditions for the oxidation. If it is cold KMnO4 then you will form a mixture of diols,

CH(CH3)-CH2-CH(OH)-CH(OH)-CH2-CH2
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You will need to check my assignments, but I make it that the two products are

(1R,2R,4R)-4-methyl-cyclohexan-1,2-diol

and

(1S,2S,4R)-4-methyl-cyclohexan-1,2-diol

Best to make models to check configuration assignments.

Where there has been cis addition of OH at each ends of the double bond. The ratio of products is unlikely to be 50:50.

It is not a racemic mixture, neither is it a meso molecule.

The products will have slightly different properties. It should be possible to separate the molecules by TLC and by column chromatography, although it may require a few extra 'tricks' to do so. I would try eluents with a small amount of water. The additional 'tricks' might be to add a transition metal to the silica for the TLC and the column. To visualise the TLC spray with permanganate and heat the plate. The diol spots will appear as pale brown/white spots.