How many optical isomers are possible on monochlorination of 2–methyl butane.
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Monochlorination of 2-methylbutane (C5H12) involves replacing one H atom with Cl. The carbon skeleton has four types of equivalent hydrogens, leading to four constitutional isomers. However, the question asks for optical isomers (enantiomers), which are chiral molecules that are non-superimposable mirror images.
Only one product, 1-chloro-2-methylbutane, is chiral because it has a carbon atom bonded to four different groups: H, Cl, CH3, and CH2CH3. A chiral center gives a pair of enantiomers (two optical isomers). The other monochlorination products are achiral.
Therefore, the number of optical isomers is 2.
Final Answer: 2