ONE-POT SYNTHESIS OF 1,5-BENZODIAZEPINE-2,3-DICARBOXYLATES <i>via</i> THREE-COMPONENT DOMINO REACTIONS IN THE PRESENCE OF γ-Fe2O3@SiO<sub>2</sub>/Ce(OTf)<sub>3</sub>

Authors

  • Xiaoying An Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024
  • Lei Gao Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024
  • Mingliang Wang Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024
  • Haitao Wu Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024
  • Lanzhi Wang Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050024

DOI:

https://doi.org/10.1007/6017

Keywords:

1, 5-benzodiazepine-2, 3-dicarboxylates, 4-diazepines, γ-Fe2O3@SiO2/Ce(OTf)3, catalysis, domino reactions, multicomponent reactions

Abstract

Novel, efficient and environmentally friendly approaches have been developed for the synthesis of 1,5-benzodiazepine-2,3-dicarboxylates by
one-pot three-component domino reactions in the presence of a catalytic amount of γ-Fe2O3@SiO2/Ce(OTf)3 in EtOH at ambient temperature. A total of 32 2,5-dihydro-1H-1,5-benzodiazepine-2,3-dicarboxylates and 2-methyl-2,3-dihydro-1H-1,5-benzodiazepine-2,3-dicarboxylates with enamine or imine structure of the heterocycle, respectively, were obtained in good yields by reacting substituted 1,2-phenylenediamine, β-carbonyl esters, and ethyl glyoxylate or ethyl pyruvate. One-pot reactions were successfully realized to form one new cycle and four new bonds (one C–C, two C–N, one C=C or two C–C, one C–N, one C=N). Furthermore, plausible mechanisms for the formation of 1,5-benzodiazepine-2,3-dicarboxylates have been proposed. The salient features of this reaction include short reaction time, mild reaction conditions, moderate to excellent yields, recyclability of the catalyst, and wide substrate scope.

Published

2021-08-26

Issue

Section

Original Papers