Ortho-toluenesulfonic acid is widely applied in the manufacture of pharmaceuticals dyes resins fragrances and specialty chemicals where it serves as an efficient acid catalyst in organic synthesis.

The primary purpose of o-TSA is to act as an acid catalyst accelerating chemical reactions such as esterification condensation dehydration and polymerization.

Ortho-toluenesulfonic acid (o-TSA) is a strong organic sulfonic acid it is commonly used as a solid acid reagent in chemical synthesis.