Thiocyanogen Solution

Abstract

All methods that have been suggested for the preparation of thiocyanogen solutions involve the use of strictly anhydrous solvents, since the presence of moisture causes rapid hydrolysis and decomposition to take place. It is possible, however, to stabilize thiocyanogen in aqueous solution to a limited extent by the presence of large quantities of potassium thiocyanate.Thiocyanogen has been prepared by the action of iodine upon an ethereal suspension of silver thi0cyanate.l This reaction does not go to completion, since thiocyanogen is a halogenoid2 lying between bromine and iodine in order of chemical activity. It can be prepared by the oxidation of a solution of hydrogen thiocyanate in ether with manganese dioxide. The electrolysis of thiocyanates in alcoholic solution results in the discharge of the thiocyanate radical and the formation of thiocyanogen as an anodic p r~d u c t .~ The interaction of plumbic acetate and thiocyanic acid in ethereal solution presumably results in the formation of plumbic thiocyanate which immediately decomposes into thiocyanogen and plumbous thio~yanate.~The action of bromine upon various metallic thiocyanates gives thiocyanogen in better yield, but few solvents yield

A Brief on Thiocyanation of N-Activated Arenes and N-Bearing Heteroaromatic Compounds

“…First, it is very significant because of its ability to transform to various sulfur-bearing functional groups such as sulfides 1 , thioesters 2 , thiophenols 3 , cyanothiolates which lead to thionitrile synthesis 4 , thiosulfonates (thiotosylates) 5 , thiols and S-acetylates 6 and thiocarbamates 7 . Second, it is a key intermediate for the synthesis of heterocyclic compounds such as thiazoles and thiazinones [8][9][10] , which are precursors of agrichemicals (for example wood preservative), dyes and drugs 11 . Third, combination of this motif with other substrates yields the other chemicals, as the crosscoupling desulfurization of aryl thiocyanates also used as a cyanide-free source for the cyanation of arylboronic acids to nitriles 12 .…”