Weinreb amide as an efficient reagent in the one pot synthesis of benzimidazoles and benzothiazoles

…, S Thamas, KSV Kumar, CSP Kumara, KS Rangappa…

Index: Bommegowda, Yadaganahalli K.; Lingaraju, Gejjalagere S.; Thamas, Saji; Vinay Kumar, Koravangala S.; Pradeepa Kumara, Challanayakanahally S.; Rangappa, Kanchugarakoppal S.; Sadashiva, Marilinganadoddi P. Tetrahedron Letters, 2013 , vol. 54, # 21 p. 2693 - 2695

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Citation Number: 17

Abstract

One pot synthesis of 2-substituted benzimidazoles/benzothiazoles through condensation is followed by cyclization of Weinreb amide with o-diaminoarene or o-aminothiophenol is reported. In the presence of boron trifluoride etherate in 1, 4-dioxane solvent, a high yield (75–94%) was achieved within 60min. Weinreb amide shows high selectivity in the reaction, even in presence of other active functional groups such as carboxyl, halogen, cyano, and ...