Abstract

Benzaldehyde is the simplest and quite possibly the most industrially useful aromatic aldehyde. It is manufactured from toluene, either by chlorination, followed by hydrolysis, or by liquid phase air oxidation. The air oxidation of toluene to produce benzoic acid is the source of most of the world's synthetic benzaldehyde.

Benzaldehyde is widely used directly, as a synthetic flavoring substance, or as a raw material in the synthesis of industrially important derivatives such as benzyl alcohol, benzoin and benzil and several benzyl amines. The hydrogenation of benzaldehyde to form benzyl alcohol is the largest single use of benzaldehyde.

In addition, benzaldehyde serves as the major raw material a wide variety of fragrance compounds are derivatives of benzaldehyde. The major products in the fragrance category are cinnamic aldehyde and a number of substituted cinnamic aldehydes; such as methyl, butyl, amyl, and hexyl cinnamic aldehydes.