p-Toluenesulfonic acid

p-Toluenesulfonic acid (PTSA, pTSA, or pTsOH) or tosylic acid (TsOH) is an <a href="/facts/Organic_compound/gqCNaN45">organic compound</a> with the formula <a href="/facts/Methyl_group/fkM97EMD">CH3</a><a href="/facts/Benzene/Fguue7nr">C6H4</a><a href="/facts/Sulfonic_acid/6JHPGnNY">SO3H</a>. It is a white extremely hygroscopic solid that is soluble in water, <a href="/facts/Alcohol_(chemistry)/Y0SCTDkh">alcohols</a>, and other <a href="/facts/Chemical_polarity/KlIJ0zjB">polar</a> organic solvents. The CH3C6H4SO2 group is known as the <a href="/facts/Tosyl/Q4qU62D1">tosyl</a> group and is often abbreviated as Ts or Tos. Most often, TsOH refers to the <a href="/facts/Monohydrate/dev82l69">monohydrate</a>, TsOH.H2O.
As with other aryl <a href="/facts/Sulfonic_acid/6JHPGnNY">sulfonic acids</a>, TsOH is a strong <a href="/facts/Organic_acid/2Pfb26Lp">organic acid</a>. It is about one million times stronger than <a href="/facts/Benzoic_acid/7HrmrBYS">benzoic acid</a>. It is one of the few strong acids that is solid and therefore is conveniently weighed and stored.

p-Toluenesulfonic acid open-in-new

p-Toluenesulfonic acid