Superelectrophilic Activation of Crotonic/Methacrylic Acids: Direct Access to Thiochroman-4-ones from Benzenethiols by Microwave-Assisted One-Pot Alkylation/ …

…, R Choudhary, F Paknia, T Mathew, GA Olah

Index: Prakash, G. K. Surya; Paknia, Farzaneh; Vaghoo, Habiba; Rasul, Golam; Mathew, Thomas; Olah, George A. Journal of Organic Chemistry, 2010 , vol. 75, # 7 p. 2219 - 2226

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Citation Number: 4

Abstract

An efficient microwave-assisted protocol for the synthesis of 2-/3-methylthiochroman-4-ones by superacid-catalyzed alkylation followed by cyclic acylation (cyclization via intramolecular acylation) is described. Using easily accessible benzenethiols and crotonic acid/methacrylic acid with triflic acid (as catalyst of choice for needed optimal acidity), the reaction was tuned toward the formation of the cyclized products in good selectivity and yield. A mechanism ...