Q3(c)(i). Acyl chloride to isocyanate; singlet and triplet nitrene
Consider the following conversion: [acyl chloride] 1) NaN₃ / inert solvent, 2) heat → R–N=C=O. Show that the above conversion involves the formation of a nitrene intermediate. Draw the orbital pictures of the singlet and triplet states of nitrene.
Answer in brief
Curtius rearrangement: the acyl azide loses N₂ to an acyl nitrene, and R migrates to the electron-deficient nitrogen.
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CoversCurtius rearrangementnitreneacyl azideisocyanatesinglet and triplet nitrene
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