title: Highly efficient water-mediated approach to access benzazoles: metal catalyst and base-free synthesis of 2-substituted benzimidazoles, benzoxazoles, and benzothiazoles.
abstract: An efficient water-catalyzed method has been developed for the synthesis of 2-substituted benzimidazoles, benzoxazoles, and benzothiazoles in one step. The present method excludes the usage of toxic metal catalysts and bases to produce benzazoles in good to excellent yields. An efficient and versatile water-mediated method has been established for the synthesis of various 2-arylbenzazoles. The present protocol excludes the usage of any catalyst and additive provided excellent selectivities and yields with high functional group tolerance for the synthesis of 2-arylated benzimidazoles, benzoxazoles, and benzothiazoles. Benzazolones were also synthesized using similar reaction protocol.
authors.affiliation: Natural Product Chemistry and Process Development Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, Himachal Pradesh, India.
authors.forename: Manju
authors.initials: M
authors.lastname: Bala
authors.forename: Praveen Kumar
authors.initials: PK
authors.lastname: Verma
authors.forename: Deepika
authors.initials: D
authors.lastname: Sharma
authors.forename: Neeraj
authors.initials: N
authors.lastname: Kumar
authors.forename: Bikram
authors.initials: B
authors.lastname: Singh
mesh_terms: D001562:Benzimidazoles / Q000138:chemical synthesis*; D052160:Benzothiazoles / Q000138:chemical synthesis*; D001583:Benzoxazoles / Q000138:chemical synthesis*; D002384:Catalysis; D008670:Metals / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D001562:Benzimidazoles; D052160:Benzothiazoles; D001583:Benzoxazoles; D008670:Metals; D014867:Water