Abstract
Indoles, oxindoles and aromatic amino compounds undergo smooth thiocyanation with ammonium thiocyanate in the presence of anhydrous FeCl3 in dichloromethane under mild conditions to afford the corresponding 3-indolyl and 4-aryl thiocyanates, respectively, in high yields with excellent selectivity. The use of ferric chloride makes it quite simple, more convenient and practical. This new method offers several advantages such as high conversions, cleaner reaction profiles, short reaction times, and the use of inexpensive and readily available catalyst.
Key words
thiocyanation - electrophilic substitution - aromatic systems - aryl thiocyanates
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