Several synthesis routes exist, the most common being the reaction between alkyl halides and alkali thiocyanate in aqueous media. Illustrative is the preparation of isopropyl thiocyanate by treatment of isopropyl bromide with sodium thiocyanate in boiling ethanol. The main complication with this route is the competing formation of alkyisothiocyanates.  "SN1-type" substrates (e.g., benzyl halides) tend to give the isothiocyanate derivatives.
Some organic thiocyanates are generated by cyanation of some organosulfur compounds.  Sulfenyl thiosulfates (RSSO) react with alkali metal cyanides to give thiocyanates with displacement of sulfite.  This approach has been applied to allyl thiocyanate:
Sulfenyl chlorides (RSCl) also convert to thiocyanates.
Aryl thiocyanates are traditionally produced by the Sandmeyer reaction, which involves combining copper(I) thiocyanate and diazonium salts:
Some arylthiocyanates can also often be obtained by thiocyanogenation, i.e. the reaction of thiocyanogen.  This reaction is favored for electron-rich aromatic substrates.