SO2OH

SO2OH is a chemical notation that may refer to several related sulfur-oxygen-hydrogen fragments, and it is not a single well-defined compound. In chemical literature, SO2H or HO-SO2 is sometimes used to denote a sulfinyl- or sulfonyl-hydroxyl fragment, and in kinetic mechanisms it may appear as an intermediate such as a hydroxy-sulfonyl species. The exact structure can vary with context, making the designation ambiguous without further specification.

Common interpretations include the sulfinic acid fragment attached to an organic residue, written as R-SO2H, where the sulfinyl moiety is bonded to the rest of the molecule. In this sense, SO2H forms part of the naming for sulfinic acids. Another interpretation is a transient radical or intermediate in atmospheric or combustion chemistry, for example a hydroxy-sulfonyl radical HO-SO2• that is proposed in reaction schemes but not isolated. Such species are typically short-lived and characterized mainly by kinetics and spectroscopy rather than by a pure, stable compound.

In inorganic and physical chemistry discussions, related species may be described as sulfurous-oxide derivatives or as reactive hydroxylated sulfonyl groups, though a stable neutral compound with the exact formula SO2OH is not generally established as a discrete substance.

Properties and reactivity:

Because SO2OH is not commonly isolated as a standalone substance, its properties are not cataloged in the same way as well-characterized compounds. When invoked as a reactive fragment or radical, its behavior is governed by radical reactivity, electrophilic sulfur centers, and potential to participate in oxidation, hydrolysis, or sulfonation-like transformations within a broader chemical system.

See also: sulfurous acid, sulfinic acids, sulfite chemistry, sulfonyl groups.