From among the following, identify the compound which forms two moles of a ketone on ozonolysis. [A] 2,3-Dimethylbutane. [B] 3-Methyl-1-pentene. [C] 2,3-Dimethyl-2-butene. [D] 2-Methyl-2-pentane.
To determine which compound forms two moles of a ketone on ozonolysis, we need to understand the process of ozonolysis and the structures of the compounds given. Ozonolysis is a reaction that breaks alkene double bonds using ozone, forming two carbonyl compounds (aldehydes or ketones) from the alkene. [A] 2,3-Dimethylbutane is an alkane (no double bonds), so it will not undergo ozonolysis. Therefore, it cannot form ketones through this process. [B] 3-Methyl-1-pentene has a double bond between the carbon atoms in the 1st and 2 nd positions. However, ozonolysis of this compound will not yield two moles of a ketone; it will likely produce a mixture of a ketone and an aldehyde, due to the nature of the substituents around the double bond. [C] 2,3-Dimethyl-2-butene is a more promising candidate because it has a double bond at the 2 nd position, and with methyl groups on both carbons involved in the double bond, ozonolysis will indeed yield two moles of the same ketone due to the symmetry of the molecule. [D] 2-Methyl-2-pentane is an alkane (no double bonds), similar to option A, and also cannot undergo ozonolysis to produce ketones. Therefore, the correct answer is Option C [2,3-Dimethyl-2-butene], as it is the only compound listed that, when subjected to ozonolysis, will form two moles of a ketone, specifically acetone in this case. The reaction proceeds by cleaving the double bond and forming two carbonyl groups, one on each of the former alkene carbon atoms, because of the symmetrically substituted double bond.