Question

Which of the following is not paramagnetic?

Options

• Carbon free radical 

• Singlet carbene

• Triplet carbene

• All of the above

Answer 1

Singlet carbene

Explanation:

\[\begin{array}{cc}\ce{H - \overset{\bullet}{C} - N}\\ |\\\ce{\underset{unpaired \bar{e}}{H}}\end{array}\]

\[\ce{\underset{Singlet carbene}{ \overset{⇅}{CH2}}}\]

\[\ce{\underset{triplet carbene unpaired \bar{e}}{\overset{\uparrow}{\uparrow CH2}}}\]