Question

How can I draw and identify the chiral centers of galactose?

Answer 1

The carbon which contains four different groups attached to it is called chiral center. Generally we can see chiral carbons in organic compounds. Chiral carbons are optically active in nature and can be detected by polarimeters.

Complete step by step answer:
- In the question it is asked how we can identify and draw the chiral centers in galactose.
- To know about the number of chiral centers in galactose we should know the structure of the galactose.
- The structure of the galactose is as follows.

- The galactose contains 6 carbons atoms and we see them from the above structure.
- The carbons which are marked with star marks (*) are chiral carbons because they contain four different groups which are attached to the carbon and make the carbon atom as chiral.
- The carbon-2, carbon-3, carbon-4 and carbon-5 are chiral carbons in galactose.
- There are two functional groups present in galactose and they are aldehyde and alcohol. They are located on carbon one and carbon 6 in the structure of the galactose.

Note: There are four chiral centers in galactose. By using a number of chiral carbons we can find the number of stereoisomers is going to form. So the number of possible stereoisomers for galactose are = ${{2}^{n}}$ , here n = number of chiral carbons. For galactose n = 4 then number of stereoisomers = ${{2}^{4}} = 16$ . Means galactose is going to form 16 stereoisomers.