13143-02-7Relevant articles and documents
A green and facile approach for the synthesis of N-monosubstituted ureas in water: Pd catalyzed reaction of arylcyanamides (an unexpected behavior of electron withdrawing groups)
Habibi, Davood,Heydari, Somayyeh,Faraji, Alireza,Keypour, Hasan,Mahmoudabadi, Masoumeh
, p. 520 - 529 (2018)
The Fe3O4 magnetic nano-particles were prepared, coated with tetraethyl orthosilicate (TEOS), functionalized with 3-chloropropyltrimethoxysilane (CPTMS), further functionalized with 2,2′-(piperazine-1,4-diylbis(methylene) dianiline (PDMD) and the corresponding Pd complex synthesized as a novel nano-magnetic heterogeneous catalyst (Fe3O4@SiO2@CPTMS@PDMD@Pd) to be used for the synthesis of various N-monosubstituted ureas in water. Also, in another attempt to see the effect of HCOOH, the hydration reaction of arylcyanamide was carried out in the presence of HCOOH (water + 98% HCOOH) which had two effects: it decreased the amount of the Pd catalyst from 40 to 30 mg, and the reaction condition was changed from the reflux condition to room temperature. Interestingly, the arylcyanamides with electron withdrawing groups influence the course of the reaction and need more reaction times for completion which is an unexpected behavior, probably due to the high electron density around the central carbon atom of the nitrile group.
Hybrid Pd/Fe3O4 nanowires: Fabrication, characterization, optical properties and application as magnetically reusable catalyst for the synthesis of N-monosubstituted ureas under ligand-free conditions
Nasrollahzadeh, Mahmoud,Azarian, Abbas,Ehsani, Ali,Sajadi, S.Mohammad,Babaei, Ferydon
, p. 168 - 175 (2014/05/20)
This paper reports the synthesis and use of Pd/Fe3O4 nanowires, as magnetically separable catalysts for ligand-free amidation coupling reactions of aryl halides with benzylurea under microwave irradiation. Then, the in situ hydrogenolysis of the products was performed to afford the N-monosubstituted ureas from good to excellent yields. This method has the advantages of high yields, simple methodology and easy work up. The catalyst can be recovered by using a magnet and reused several times without significant loss of its catalytic activity. The catalyst was characterized using the powder XRD, SEM, EDS and UV-vis spectroscopy. Experimental absorbance spectra was compared with results from the Gans theory.