Chapter 17, Problem 17.38P

Interpretation Introduction

Interpretation:

It is to be verified whether imine is reduced in the given reaction, by calculating the oxidation state of the carbon and nitrogen atoms of the $\text{C}=\text{N}$ group before and after the reaction. Further, it is to be determined whether imine gains electrons, and if so, how many.

Concept introduction:

The oxidation state of an atom can be calculated using two steps.

First is to assign proper number of valence electrons to the atom. In this case, both electrons of a lone pair are assigned to the atom on which they appear. In a covalent bond, all the electrons are assigned to the more electronegative atom. If the two bonded atoms are the same or have comparable electronegativities, then electrons get divided equally to both the atoms.

Second is by comparing the assigned valence electrons to an atom to the atom’s group number. In this, each excess electron contributes -1 charge, while each electron the atom is lacking contributes +1 charge to the oxidation state.

If a reactant species has a carbon atom that gains a bond to $\text{H}$ or loses a bond to $\text{O}$ during the course of the reaction, that species is typically undergoing reduction.