Phosphinic acid is H3PO2.
Phosphinic acid
A phosphorus oxoacid consists of single pentavalent phosphorus covalently bound via single bonds to two hydrogens and a hydroxy group and a double bond to an oxygen. Hypophosphorous acid (HPA), or phosphinic acid, is a phosphorus oxyacid and a powerful reducing agent with the molecular formula H3PO2. It is a colourless low-melting compound, which is soluble in water, dioxane, and alcohols.