Which combination of an aldehyde and an alcohol most readily

Which combination of an aldehyde and an alcohol most readily forms a hemiacetal with base catalysis? A o + CH3CH20H CHH (CH3)2CHOH CH3 +(CH3)2CHOH

Solution

Answer is option C.

In option C the carbonyl compound is activated by the presence of electron withdrawing chlorine atom and less bulky ethanol can attack more easily compare to more bulky isopropanol.

In other option either the carbonyl is less activated or the alcohol is bulky therefore

Answer is option C.