Thiocyanation of aromatic and heteroaromatic compounds using polymer-supported thiocyanate ion as the versatile reagent and ceric ammonium nitrate as the versatile single-electron oxidant

Indoles, pyrrole aniline derivatives and aromatic amino compounds undergo smooth thiocyanation with cross-linked poly (4-vinylpyridine) supported thiocyanate ion, [P-4-VP]SCN in the presence of ceric ammonium nitrate (CAN) as a versatile single-electron oxidant in ethanol at room temperature to afford the corresponding 3-indolyl 2-pyroyl and 4-aryl thiocyanates, respectively, in high to excellent yields with excellent selectivity in a short reaction time. The use of [P-4-VP]SCN/CAN makes it quite simple, more convenient, and practical. The present procedure offers advantages such as short reaction time, simple reaction work-up, and the polymeric reagents can be regenerated and reused for several times without significant loss of their activity. [GRAPHICS]