Q. 5-5-60E - Organic Chemistry (Mcmurry)

Question

The first step in the metabolism of glycerol, formed by digestion of fats, is phosphorylation of the pro-R   $\mathbf{-}{\mathbf{CH}}_{\mathbf{2}}\mathbf{OH}$  group by reaction with adenosine triphosphate (ATP) to give the corresponding glycerol phosphate plus adenosine diphosphate (ADP). Show the stereochemistry of the product.

                       

Step-by-Step Solution

Answer

The stereochemistry of the product is shown below. 

Stereochemistry

Stereochemistry is the branch of chemistry that deals with the different spatial arrangements of atoms present in a molecule. The R and S configuration of a molecule can be designated by seeing the stereochemistry of a molecule.

The stereochemistry of the product

The upper $-{\mathrm{CH}}_2\mathrm{OH}$ is designated as pro-S, and the lower  $-{\mathrm{CH}}_2\mathrm{OH}$ is designated as pro-R. The reaction of glycerol with ATP generates glycerol phosphate and adenosine diphosphate. The pro-R   $-{\mathrm{CH}}_2\mathrm{OH}$ group of glycerol converts into  $-{\mathrm{CH}}_2{{\mathrm{OPO}}_3}^{2-}$ and forms glycerol phosphate. The central chiral carbon has an R configuration.

                                 

                                          Metabolism of glycerol