Ionic liquid catalyzed Ritter reaction/Pd-catalyzed directed Ortho-arylation; facile access to diverse libraries of biaryl-amides from Aryl-nitriles

Authors

Suraj M. Sutar, Karnatak University
Hemantkumar M. Savanur, P.C. Jabin Science College
Rajesh G. Kalkhambkar, Karnatak University
Gabriela L. Borosky, Instituto de Investigaciones en Fisicoquímica de Cordoba
Gopalakrishnan Aridoss, Ton-Duc-Thang UniversityFollow
Kenneth K. Laali, University of North FloridaFollow

Document Type

Article

Publication Date

12-10-2020

Abstract

Diverse libraries of biaryl-amides bearing N-t-butyl and N-adamantyl groups were synthesized in two steps by the Ritter reaction of aryl-nitriles, using tBuOH and AdaOH as carbocation precursors, and employing [BMIM(SO3H)][OTf] (neat or with [BMIM][PF6] as co-solvent) or tetramethyl guanidinium-ILs [TMG][X] (X = CF3COO, EtOSO3) as dual catalyst/solvent, followed by a Pd-catalyzed directed regioselective ortho[sbnd]C[sbnd]H arylation of the Ritter amides with Ar-X (X = I, Cl). The feasibility to perform the two-steps in sequence is also demonstrated, and potential for recycling/reuse of the ILs is also shown. Preference for [Pd] coordination to the amide carbonyl versus amide nitrogen is borne out by DFT computations.

Publication Title

Tetrahedron Letters

Volume

61

Issue

50

Digital Object Identifier (DOI)

10.1016/j.tetlet.2020.152553

ISSN

00404039

E-ISSN

18733581

Citation Information

Sutar, S. M., Savanur, H. M., Kalkhambkar, R. G., Borosky, G. L., Aridoss, G., Laali, K. K. (2020) Ionic Liquid Catalyzed Ritter Reaction/Pd-catalyzed Directed Ortho-arylation; Facile Access to Diverse Libraries of Biaryl-Amides from Aryl-N. Nitriles. (2020) Tetrahedron Letters, 61(50), 152553