The Mechanism of Pyrolysis of Benzyl Azide: Spectroscopic Evidence for Benzenemethanimine Formation

We study the gas-phase pyrolysis of benzyl azide (BA, C₆H₅CH₂N₃) using ultraviolet photoelectron spectroscopy (UVPES) and matrix-isolation infrared (IR) spectroscopy, together with electronic structure calculations and Rice–Ramsperger–Kassel–Marcus (RRKM) calculations. It is found that BA decomposes via N₂ elimination at ca. 615 K, primarily yielding benzenemethaninime. Other end products include HCN and C₆H₆. N-Methyleneaniline is not detected, although its formation at higher temperature is foreseen by RRKM calculations.