Later in his career, he reported the synthesis of the pyridine-N-oxide.

This pyridine-N-oxide undergoes a rearrangement reaction to 2-pyridone in acetic anhydride:

Pyridine-N-oxide is the heterocyclic compound with the formula CHNO.

They can be promoted, however, using clever experimental techniques, such as conducting electrophilic substitution on the pyridine-N-oxide followed by deoxygenation of the nitrogen atom.

The tin atom has distorted trigonal bipyramidal coordination with the isocyanate group and pyridine-N-oxide at the apices of the bipyramid and phenyl rings in the equatorial positions.