Question

Which one of the following is the correct order of -I effect?

• A. $-N{R}_2<-OR>-F$
• B. $-N{R}_2>-OR>-F$
• C. $-N{R}_2<-OR<-F$
• D. $-N{R}_2>-OR<-F$

Answer 1

The correct option is C $-N{R}_2<-OR<-F$

More electronegativity of the attached group with the carbon atom means more it will show -I effect as it has more tendency to withdraw electron.
The correct order of increasing electronegativity of atom is $N<O<F$ and hence the correct order of negative inductive effect is $-N{R}_2<-OR<-F$ i.e. option (c)