Reactivity of bis(arylcarbamoyl)-N-arylphenacylamine oximes. Synthesis of 1,3-dihydroimidazol-2-ones and N-unsubstituted O-arylcarbamoylhydroxylamines

Supramolecular architecture of phenylcarbamoylated acetone oxime 1,1-diisopropyl-3-phenylurea] complex

“…The products were again those obtained from the reaction with compounds 1 (Scheme 1, method B). 1 The cyclization possibility was excluded, since there were IR bands corresponding to the oxime C=N stretching and on the other hand, the shifts of the NH and C=O bands of compound 1 to higher frequencies was observed when the spectra 1 N,N-Diethyl-N -phenylurea and acetophenone oxime were refluxed in THF for 24 h and no trace of 1 was obtained however when the reaction was performed in the presence of equimolar amount of DMAD the reaction proceeds for short time and the products were dimethyl N,N-dialkylaminomaleate and corresponding phenylcarbamoylated acetophenone oxime (for more information see: Coşkun, N.; Arıkan, N. Turk. J.…”

“…IR spectra were recorded on a Mattson 1000 FTIR. 1 H and 13 C NMR spectra were recorded on a Bruker Dpx 400 MHz spectrometer. All spectra were taken in deuteriochloroform.…”

“…Recently, we had reported the synthesis of Oarylcarbamoylhydroxylammonium tosylates [1] in high yields and their applications in the synthesis of nitriles [2]. Although examples of 2-substituted-1,2,4-oxadiazolidin-5-ones and -thiones [3][4][5][6] and tetrahydroimidazo [1,5-b] [1,2,4]oxadiazol-2(1H)-ones [7,8] and thiones [9,10] are known in the literature, examples of 2-unsubstituted-1,2,4-oxadiazolidin-5-ones are absent.…”

“…Although examples of 2-substituted-1,2,4-oxadiazolidin-5-ones and -thiones [3][4][5][6] and tetrahydroimidazo [1,5-b] [1,2,4]oxadiazol-2(1H)-ones [7,8] and thiones [9,10] are known in the literature, examples of 2-unsubstituted-1,2,4-oxadiazolidin-5-ones are absent. Lycoposerramine-A, is a recently reported alkaloid which has a 4-unsubstituted-1,2,4-oxadiazolidin-5-one residue in the molecule [11].…”

“…O-Arylcarbamoylated hydroxylammonium tosylates react with ketones in ethanol at room temperature to give the corresponding carbamoylated oximes in quantitative yields. Attempts to cyclize the corresponding O-carbamoylated oximes in refluxing THF in the presence of TsOH were unsuccessful [1]. Attempts to induce cyclization using bases as KOH and LDA at different conditions failed.…”