Question

I: $C{H}_2=CHC{H}_{2}N{H}_2,$ II:$C{H}_{3}C{H}_{2}C{H}_{2}N{H}_2,$III: $CH\equiv CC{H}_{2}N{H}_2$

What is the correct order of basicity of the above compounds?

• A. I $>$ II $>$ III
• B. II $>$ I $>$ III
• C. III $>$ II $>$ I
• D. II $<$ III $<$ I

Answer 1

Answer: (B)

II $>$ I $>$ III

For the basicity of compounds, specially amines, the $+I$ Effect on them is counted. Basicity is directly proportionality to the $+I$ effect.

Among the given compounds, maximum $+I$ effect is present in (II) as it is an alkyl group. Minimum $+I$effect is present in (III) as $CH\equiv C-$ group is present.

So, (II) compound is most basic and (III) is least basic among the given compounds.

$II>I>III$