Exploding bomb with nitro compound

Incident

Sealed bomb at 160°C exploded, damaging equipment and fume cupboard

The Investigation

A 4 gram prep was being scaled up in Medicinal Chemistry Department to 20 g. The reaction was a chloronitrotoluene derivative being oxidised to the acid with nitric acid in a sealed bomb at 160°C. After 2 hours the bomb exploded.

Probable Cause and Follow Up

Decomposition of unstable nitro compounds, possibly OK with smaller scale - easier loss of heat, and gas production not so critical.

Lab procedures, etc., being re-defined.