title: Heterogeneously porous γ-MnO₂-catalyzed direct oxidative amination of benzoxazole through C-H activation in the presence of O₂.
abstract: Oxidative amination of azoles through catalytic C-H bond activation is a very important reaction due to the presence of 2-aminoazoles in several biologically active compounds. However, most of the reported methods are performed under homogeneous reaction conditions using excess reagents and additives. Herein, we report the heterogeneous, porous γ-MnO2-catalyzed direct amination of benzoxazole with wide range of primary and secondary amines. The amination was carried under mild reaction conditions and using molecular oxygen as a green oxidant, without any additives. The catalyst can easily be separated by filtration and reused several times without a significant loss of its catalytic performance. Of note, the reaction tolerates a functional group such as alcohol, thus indicating the broad applicability of this reaction.
authors.affiliation: Discipline of Inorganic Materials and Catalysis, & Academy of Scientific and Innovative Research, Central Salt and Marine Chemicals Research Institute (CSIR), G.B. Marg, Bhavnagar-364002, Gujarat (India), Fax: (+91) 278-2567562.
authors.forename: Provas
authors.initials: P
authors.lastname: Pal
authors.forename: Arnab Kanti
authors.initials: AK
authors.lastname: Giri
authors.forename: Harshvardhan
authors.initials: H
authors.lastname: Singh
authors.forename: Subhash Chandra
authors.initials: SC
authors.lastname: Ghosh
authors.forename: Asit Baran
authors.initials: AB
authors.lastname: Panda
keywords: CH activation; amination; benzoxazole; heterogeneous catalysis; manganese