p-Toluenesulfinic acid sodium salt tetrahydrate

P-TOLUENESULFINIC ACID SODIUM SALT TETRAHYDRATE (Na+·C7H7O2S·4H2O) is a white crystalline powder. The crystal structure is dominated by hydrogen bonds. Except for one of the hydrogen atoms on one water molecule that is part of a O–H···π interaction, all of the water molecules take part in O–H···O hydrogen bonding. Each of the sulfinic acid group's O atoms acts as multifold acceptor. The molecular geometry around the sulfate atom is tetrahedral, with X–S–Y angles ranging from 102.23(6) to 110.04(6). In the crystal, the water molecules link the sodium cations into chains along the b-axis via O—H hydrogen bonds.  In total, the components of the crystal structure are connected to double layers perpendicular to the crystallographic a axis with the hydrophobic aromatic moieties forming the outer surfaces of these layers. π-Stacking is not a prominent feature of the crystal structure with the shortest distance between two aromatic systems found at 5.5359 (11) Å[1].

Sodium p-toluenesulfinate Hydrate is used in organic chemical reactions as an alkylating agent, non-oxidizing catalyst, intermediate for the synthesis of biologically active compounds. of grades are available including Mil Spec (military grade), ACS, Reagent and Technical Grade, Food, Agricultural and Pharmaceutical Grade, Optical Grade, USP and EP/BP (European Pharmacopoeia/British Pharmacopoeia).

The aryl sulfonyl chloride (10.0 mmol, 1.0 equiv) was dissolved in 30 mL water. Sodium sulfite (16.0 mmol, 1.6 equiv) and sodium bicarbonate (16.0 mmol, 1.6 equiv) were added, and the reaction mixture was refluxed for 3 h. The water was evaporated, and ethanol was added to the residue. The suspension was heated for 10 min, cooled, and filtered through a 20 μm polyethylene frit. This was repeated twice with the residue from the filtration. The ethanol fractions were combined, and the solvent was evaporated under vacuum, The sodium arylsulfinates were isolated as white powders.

[1] Richard Betz, Thomas G. (2011). Sodium p-toluenesulfinate tetra-hydrate. Acta Crystallographica. Section E, Structure Reports Online, 67 Pt 7, m898. https://doi.org/10.1107/s1600536811021738