[3] Propionaldehyde exhibits the reactions characteristic of alkyl aldehydes, e.g. hydrogenation, aldol condensations, oxidations, etc.

Rising demand for non-chlorocarbon solvents has caused some manufacturers to substitutively brominate n‑propanol to propyl bromide.

However, the majority of applications use n‑propanol proper in esters or glycol ethers, or as a gentle alkylant for primary and secondary amines.

[6] Propionaldehyde along with acrolein has been detected in the molecular cloud Sagittarius B2 near the center of the Milky Way Galaxy, about 26,000 light years from Earth.

[10][11][12] With an LD50 of 1690 mg/kg (oral),[2] propionaldehyde exhibits low acute toxicity, but is a lung and eye irritant and is a combustible liquid.