Allyl thiocyanate isomerizes to the isothiocyanate:
Isothiocyanates can be prepared by degradation of dithiocarbamate salts, e.g. induced with lead nitrate.
A related method is tosyl chloride-mediated decomposition of dithiocarbamate salts.
Isothiocyanates may also be accessed by the fragmentation reactions of 1,4,2-oxathiazoles. This methodology has been applied to a polymer-supported synthesis of isothiocyanates.