Comparative Studies of Catalytic Application of Cerium(III) Chloride and Resin Supported Cerium(III) in Domino Syntheses of 1,5-Benzodiazepine and 1,3-Diazine Skeletons
| Authors | |
|---|---|
| Year of publication | 2014 |
| Type | Article in Periodical |
| Magazine / Source | Journal of Chemical Engineering and Chemistry Research |
| MU Faculty or unit | |
| Citation | |
| Web | https://www.researchgate.net/publication/267390365_Comparative_Studies_of_Catalytic_Application_of_Cerium%28III%29_Chloride_and_Resin_Supported_Cerium%28III%29_in_Domino_Syntheses_of_15-Benzodiazepine_and_13-Diazine_Skeletons |
| Field | Organic chemistry |
| Keywords | Dihydropyrimidinones; 1.5-Benzodiazepines; Metal Catalysis; Polymer Supported Ce(III); Solid Support Catalysis |
| Description | We report on results of comparative studies of catalytic application of new green catalyst, i. e. cerium(III) supported on weekly acidic cation exchanger resin of polyacrylate typein view of the known catalysts based on cerium(III) chloride (free salt in the heptahydrate form eventually doped by sodium iodide or supported on silica gel) in domino syntheses of 2,3-dihydro-1H-1,5-benzodiazepines and 3,4-dihydropyrimidin-2(1H)-ones. Catalyzed domino synthesis of four model 2,3-dihydro-1H-1,5-benzodiazepines were carried out by the solvent free reaction of o-phenylenediamine with corresponding acyclic or cyclic ketone in molar ratio 1:2:2 at room temperature. Three selected 5-ethoxycarbonyl-4-aryl-3,4-dihydropyrimidin-2(1H)-ones were prepared in catalyzed domino three-component synthesis by reaction of ethyl acetoacetate, corresponding benzaldehyde and urea in molar ratio 1:1:3 under boiling in ethanol. The title products were obtained under studied catalytic conditions in very good yields and their identity was confirmed. It was found that the efficiency of the catalytic systems in the syntheses of title benzodiazepines depend on the electron effect of substituents present in the starting benzaldehydes. To confirm the capability of new catalytic system, the above mentioned domino syntheses were realized also without the catalyst but this setup led usually to worse results. Further, it was found that the cerium(III) cation supported on the resin proved to be at least as effective as other used catalytic systems and it is inexpensive, stable, can be easily recycled and reused. Finally, application of cerium(III) supported on low-cost industrial resin further increases green impact of studied domino syntheses for the both title compound class. |
| Related projects: |