DMSO is a solvent option in selected cyanide-related chemistry. A published preparation of alpha-cyano-3-phenoxybenzyl alcohol lists it among possible solvents for a specific cyanohydrin process.
Identify the reaction type
Cyanohydrin formation adds cyanide to a carbonyl substrate. This is different from substitution on an alkyl electrophile or metal-catalyzed aryl cyanation. The substrate and cyanide system must be identified before the solvent can be assessed.
Cyanide-salt solubility depends on the counterion, water and temperature. The actual mixture may require attention to solids dispersion and mass transfer.
Containment and work-up are part of selection
Acidification of cyanide-containing material can release highly toxic hydrogen cyanide. Keep this specific hazard within the assessed process controls. DMSO can also facilitate skin uptake of dissolved substances, making contamination prevention important.
Evaluate conversion, nitrile or cyanohydrin product quality, residual cyanide control and waste treatment. Water and solvent-impurity limits must follow the established route.
The cited solvent option is evidence for that disclosed process, not a preferred DMSO medium for every cyanation. A sourcing enquiry should specify the actual reaction and solvent requirement.