What products are formed from hydration of 4-methyl cyclopentane? What can you say about the relative amounts of the products?

To draw the reaction of 4-methyl cyclopentane with water and acid.

The result is a set of 3 stereoisomers.

A key concept for the next question is that there is no energy difference between two enantiomers. Twodiastereomers are different in energy. Therefore, any two molecules that are enantiomers will be produced in equalamounts whereas any two diastereomers will be produced in different amounts.

We must look at the four possible products from this reaction and determine which are enantiomeric pairs andwhich are diastereomeric pairs. Remember, enantiomers have an inversion across all stereocenters anddiastereomers can have any combination excluding all of the stereocenters inverted.Therefore, we have the following relationship:B and C are enantiomers.A is a diastereomer of both B and CStructure A is a special kind of stereoisomer. This structure has a plane of symmetry so it is meso. Any mesostructureis achiral.

Remember that any two molecules that are enantiomers will be produced in equal amounts whereas any twodiastereomers will be produced in different amounts. We can simply say that those molecules that are enantiomerswill be produced in equal amounts and those molecules that are diastereomers will be produced in differentamounts. Thus, the relative amounts will be summarized in the following diagram.Structures B and C will be produced in the same amount. Structure A will be produced in a different amount fromB and C.