Which one of the nitrogen atoms in `underset("I")(H_(2)N)-underset("II")(NH)-oversetoverset(O)(||)(C)-underset("III")(NH_(2))` is the most nucleophilic?

Options

A. III
B. I
C. II
D. All three nitrogen atoms

Answer

B

Explanation

`H_(2)overset(..)N-overset(..)NH-oversetoverset(O)(||)(C)-overset(..)NH_(2)harrH_(2)overset(..)N-overset(..)NH-oversetoverset(O^(-))(||)(C)-overset(+)(N)H_(2)harrH_(2)overset(..)N-overset(+)(N)H-oversetoverset(O^(-))(||)(C)-overset(..)NH_(2)`
The `-NH_(2)` group away from `-oversetoverset(O)(||)(C)-` group is not involved in resonance. Hence, its lone pair is readily available.