A direct synthesis of aryl thiocyanates using cerium(IV) ammonium nitrate

Simple and Highly Efficient Catalytic Thiocyanation of Aromatic Compounds in Aqueous Media

“…On the other hand, the nucleophilic attack of thiocyanate ion at an aromatic nucleus via displacement reactions is not an easy way to form thiocyanated compounds [2 -5]. So, several methods have been developed for the electrophilic thiocyanation of arenes [6] [7] such as bromine/potassium thiocyanate [8], N-thiocyanatosuccinimide [9], an thiocyanate salt in the presence of ceric ammonium nitrate (CAN) [10], acidic montmorillonite K10 clay [11], I 2 /MeOH [2], Oxone [12], pentavalent iodine, i.e., 2-iodoxybenzoic acid (IBX) [13], or potassium peroxydisulfate/copper(II) sulfate [14]. However, these methodologies suffer from one or more drawbacks such as the use of toxic transition metals as oxidants [1], the toxicity of reagents in general [7] [8], large excess of catalyst [11], and performances under certain special conditions.…”

Five‐Membered Heterocycles: Pyrrole and Related Systems

“…Thiocyanation of pyrroles with cupric thiocyanate [278,279], thiocyanogen chloride [276] or, more conveniently, ammonium thiocyanate in the presence of iodine in methanol [280] or CAN [281], provides access to 2-thiocyanatopyrroles. 4.5.1.6 Acylation Several useful procedures for N-acylation of pyrroles are available, for example by acyl transfer from 1-acetylimidazole, which offers an efficient route to 1-acetylpyrrole [282].…”

Quinolinium bound chromium(VI) reagents for efficient electrophilic aromatic nitration and thiocyanation reactions using sodium nitrate and ammonium thiocyanate

“…The unspent acids left out in these protocols often cause environmental pollution. In recent years, several new approaches have been developed to control the regiochemistry of the reactions [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20].…”