Facile access to libraries of diversely substituted 2-aryl-benzoxazoles/benzothiazoles from readily accessible aldimines via cyclization/cross coupling in imidazolium-ILs with Pd(OAc)2 or NiCl2 (dppp) as catalyst
Document Type
Article
Publication Date
2-6-2020
Abstract
A two-step protocol involving Pd-catalyzed cyclization of readily accessible p-bromophenyl-aldimines to 2-bromophenyl-benzoxazole/benzothiazole in [BMIM][PF6] or [BMIM][BF4] as solvent, followed by the Suzuki, Heck, and Sonogashira cross-coupling reactions catalyzed by Pd or Ni is described that generates libraries of diversely substituted 2-aryl-/heteroaryl-benzoxazoles/benzothiazoles in respectable isolated yields under mild reaction conditions. The feasibility to perform the two-steps in sequence in one-pot starting from the aldimines is also demonstrated and the potential for recycling/reuse of the IL solvent is also shown.
Publication Title
Tetrahedron Letters
Volume
61
Issue
6
Digital Object Identifier (DOI)
10.1016/j.tetlet.2019.151509
ISSN
00404039
E-ISSN
18733581
Citation Information
Malunavar, S.S., Sutar, S.M., Savanur, H.M., Kalkhambkar, R.G., Laali, K.K. (2020) Facile access to libraries of diversely substituted 2-aryl-benzoxazoles/benzothiazoles from readily accessible aldimines via cyclization/cross coupling in imidazolium-ILs with Pd(OAc)2 or NiCl2 (dppp) as catalyst. Tetrahedron Letters, 61(6), 151509.