A Two‐step Anodic Thiocyanation of Alkenes in Formic Acid

Abstract

Initial formation of thiocyanogen [(SCN)2] by controlled potential anodic oxidation of NH4SCN in formic acid‐LiClO4 followed by addition of alkene as a second step, has been investigated for eight alkene derivatives. The results indicate that major products from most of the alkenes studied are addition products involving thiocyanate and formate groups. Also minor products of addition of isothiocyanate and thiocyanate groups, and allylic thiocyanates as substitution derivatives, were formed.

Electrochemical Synthesis of α-Thiocyanated/Methoxylated Ketones Using Enol Acetates

“…When AcOH was not added, only 60% yield was obtained (entry 3). The lack of acid was not conducive to free radical • SCN formation . In addition, the reaction with the electrolyte Bu 4 NI was less effective than that with KI (entry 4).…”

Recent advances in photochemical and electrochemically induced thiocyanation: a greener approach for SCN-containing compound formation

“…Becker et al devised a two-step anodic oxidation approach for the thiocyanation of olefins 102 in 2016. 43 First, ammonium thiocyanate was utilized as a source of thiocyanic acid in a separation cell with formic acid as a solvent and lithium perchlorate (LiClO 4 ), and thiocyanogen (SCN) 2 was formed through anodic oxidation in a constant voltage mode at 1.25 V. They used a platinum sheet as the anode, a steel sheet as the counter electrode, and Ag/AgCl as the reference electrode. Olefin derivatives were introduced and oxidized by free radicals.…”

Thiocyanate promoted difunctionalization and cyclization of unsaturated C–C bonds to construct 1-sulfur-2-nitrogen-functionalized alkenes and 2-thiocyanate indolines

“…2 In addition, thiocyanates can be used as sulfur and nitrile nucleophiles to construct biologically active heterocycles such as pyrimidines and thiazoles. 3 Meanwhile, isothiocyanate is not only an intermediate for the synthesis of antimicrobial and medically active substances, but also an organic dye for the immunoglobulin biomarker. 4 However, compounds containing both thiocyanate and isothiocyanate are rare and have never been commercially available due to their less controllable selectivity.…”