Autoignition of the substance on contact with moist air
name: The exothermic interaction of organolithium reagents with atmospheric moisture leads to the formation of methane, which ignites in air
n-Butyllithium reacting in air 2.5 M solution in hexane
Tert-Butyllithium -PYROPHORIC LIQUID (class 4.2-ADR)
by Davide Aufiero
Fire and Flame 34 - Methyl Lithium
Wear eye protection goggles. Use gloves. Flammable!
Always follow general safety
recommendations. Please note that conducting chemistry
experiments you must comply with the relevant legal procedures in
AlkLi + H2O → LiOH + AlkH
AlkH + O2 → CO2 + H2O
AlkLi + O2 → AlkOOLi
CH3Li + H2O → LiOH + CH4
CH4 + 2 O2 → CO2 + 2 H2O
CH3Li + O2 → CH3OOLi
C4H9Li + H2O → LiOH + C4H10
2 C4H10 + 9 O2 → 8 CO2 + 10 H2O
C4H9Li + O2 → C4H9OOLi
- Use a syringe or other container, isolated from the atmosphere, to collect several milliliters of the solution of an organolithium compound (methyllithium or n-butyllithium or tert-butyllithium). The experiment will be most spectacular, if you take methyllithium and take the substance in its pure form (not the solution).
- Release the substance into the atmosphere.
- Observe the auto-ignition of the substance.
Organolithium compounds are very reactive and are widely used in organic synthesis. High reactivity is due to the low strength of the C-Li bond and the presence of a partial negative charge on carbon. In air organolithium compounds react with many of its components, such as oxygen, moisture and carbon dioxide. The main reaction is the hydrolysis reaction with air moisture. The reaction is very exothermic, so the resulting hydrocarbon ignites spontaneously.