Which of the following is not corrrect?

Options

A. A teriary amine `(R^(1)R^(2)R^(2)N: )` exsits as a pair of enantiomers
B. A carbonion `(R^(1)R^(2)R^(3)C^(-): )` exists as a pair of enantiomers
C. both `(1)`and `(2)`
D. Tricovalent `S` and `P` compounds can be isolated as enantiomers

Answer

C

Explanation

Theoretically it can exist as a pair of enantiomers but not in practice

A rapid ''umberalla'' type inversion converts either enantiomer to a racemic mixture. At room temperature the energy required for this inversion is very low and is easily available through thermal motion of molecules.
Thus racemization is unavoidable and the enantiomers can't be isolated or separated. Consider the following tricovalent `S` and `P` compounds:
`underset("Sulphoxide")underset(":O:")underset(||)(R^(1)-ddotS-R^(2))[underset("Sulphonium")underset(R^(3))underset(||)(R^(1)-overset(+)ddotS-R^(2))]X^(-)underset("Phosphine")underset(R^(3))underset(|)(R^(1)-ddotP-R^(2))`
Trivalent `S` and `P` atoms have four `sp^(3)` hybrid orbitals. There are used for bonding and the fourth one holds the lone pair .When central `S` or `P` atoms are each bonded to three different ligands, they act as sterocenters. Unlike second period elements `(N` and `C`), the enegry required for inversion about third priod elements `(S` and `P)` is sufficiently high and thus enantiomers can be isolated or separated.