Question

An organic compound having carbon attached to four different groups is optically active. But, is the opposite also true? That is, do all optically active organic compounds have chiral carbons? Not necessarily. The presence or absence of a chiral center is not a sufficient criterion for optical activity. The ultimate criterion is the presence or absence of either plane or center of symmetry. Two compounds that are non-superimposable mirror images of each other are called enantiomers. If a compound contains more than one chiral carbon, new words are required to describe the relationship between various stereoisomers of the compounds. Those words are diastereomers and mesomers.
Optically active compounds among the following are:
A.$C{H_3} - C{H_2} - CH(Cl) - C{H_2} - C{H_3}$
B.$C{H_3} - C{H_2} - CD(Cl) - C{H_2} - C{H_3}$
C.$C{H_3} - C{H_2} - CH(D) - C{H_2} - C{H_3}$
D.$C{H_3} - C{H_2} - CH(D) - C{H_3}$

Answer 1

Hint: In this question, we will be learning all about the organic compound carbon, its behavior, and properties. In this, we will be learning all about the stereoisomers, mesomers, and many more chemical properties and which compound is optically active based on these properties.

Complete step by step solution:
We will first understand different terms in stereochemistry to come to an answer,
Now, mesomers are the kind of natural mixes in which two chiral carbons are available and those two are comparable. The net pivot of plain captivated light because of this explanation is zero for these mixes. Model: 2, 4 pentanediol. Now another important phenomenon is optically active carbon, $C$ has 4 valence electrons thus it can shape 4 bonds. When these four bonds are shaped with four distinct gatherings in a hydrocarbon then it is called chiral carbon. Compounds having chiral carbon are commonly optically dynamic, which means they can bend their pole polarity.
x= optical center
Subsequently, the compound in option D has an asymmetric carbon atom as all the four valencies of carbon shown by 'x' are fulfilled by four different groups.

Thus the compound in option D is optically active.

Note: To answer this question one needs to know the concept of organic chemistry in detail. They need to know all about the concept of stereoisomers. Diastereomers and mesomers. They need to know all the properties of Carbon and all the behaviors of Carbon. if a carbon contains four different groups attached to it then it is optically active.