title: Pd-catalyzed regioselective arylation on the C-5 position of N-aryl 1,2,3-triazoles.
abstract: We herein report a highly efficient method for the arylation at the C-5 position of N-aryl 1,2,3-triazoles via a direct palladium catalyzed arylation reaction. The optimal reaction conditions required a combination of Pd(OAc)2 and tris(o-tolyl)phosphine as catalyst, and Cs2CO3 as the base under inert atmosphere. A variety of C-5 substituted N-aryl 1,2,3-triazoles were prepared using these conditions with yields in the 70-88% range. Regioselective C-5 arylations were also performed on 1,4-disubstituted 1,2,3-triazoles. The regioselectivity in triazole substitution at the C-5 position was confirmed by single crystal XRD. In addition, computational investigations of key steps of the catalytic cycle using the density functional theory have provided a rationalization to the selective C-5 arylation of N-aryl 1,2,3-triazoles.
authors.affiliation: †Department of Applied Chemistry, Defence Institute of Advanced Technology (DU), Girinagar, Pune-411025, India.
authors.forename: K Durga Bhaskar
authors.initials: KD
authors.lastname: Yamajala
authors.affiliation: ‡Department of Chemistry, UM-DAE Centre for Excellence in Basic Sciences, Health Centre, University of Mumbai, Vidyanagari Campus, Kalina, Santacruz(E), Mumbai 400098, India.
authors.forename: Mahendra
authors.initials: M
authors.lastname: Patil
authors.affiliation: †Department of Applied Chemistry, Defence Institute of Advanced Technology (DU), Girinagar, Pune-411025, India.
authors.forename: Shaibal
authors.initials: S
authors.lastname: Banerjee
mesh_terms: D002384:Catalysis; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D011789:Quantum Theory; D013237:Stereoisomerism; D014230:Triazoles / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D009942:Organometallic Compounds; D014230:Triazoles; D010165:Palladium