New phosphonium molybdate‐promoted green, fast and selective catalytic procedure for the synthesis of trisubstituted imidazoles

Abstract

The compound 1,1′‐(ethane,1,2‐diyl)ditriphenylphosphonium hexamolybdate dimethylsulfoxide {C2H4[P(C6H5)3]2}{Mo6O19}·SO (CH3)2 (I) was prepared, and 1H‐NMR, 13C‐NMR, Fourier transform‐infrared, differential scanning calorimetry and single crystal X‐ray diffraction analysis were used to characterize the titled compound. Crystallographic data showed that compound I crystallized in the monoclinic crystal system in C2/c space group. The compound (I) was used for selective synthesis of 2,4,5‐tri aryl imidazole derivatives under solvent‐free conditions efficiently. Because of hindrance of the catalyst, the yields of products for aldehydes bearing para substituents are higher than the aldehydes bearing ortho substituents, and for aromatic aldehydes with meta substituents are very low.

New phosphonium bromobismuthate as selective catalytic reagent in the heterocyclization reactions

“…The geometry of dications (bond lengths and angles) is general and comparable with our previously reported structures. [ 42–45 ] The molecular structure of bromobismuthate anion, [Bi 2 Br 9 ] 3− is well‐known. [ 39 ] The Bi‐Br interatomic distances are in two major categories of terminal (Brt) and bridging (Brb) halogen atoms.…”

“…In this article, we tried to investigate the phosphonium‐bromobismuthate structural correlations in the title compound and the other hybrids reported in the Cambridge Structural Database (CSD). In addition, following our previous studies on the applications of quaternary phosphonium derivatives, [ 42–46 ] herein we report a selective, simple, and fast method for the synthesis of benzimidazole and benzoxazole derivatives using title compound as a heterogenous Lewis acid catalyst under solvent‐free conditions. As far as we know, there is no example of using bismuth compounds as catalyst for the synthesis of the abovementioned heterocycles.…”

Synthesis, Characterization, Molecular Docking, and Investigation of Antibacterial Properties of New Derivatives of 1‐H‐Phenanthro [9,10‐d] Imidazole

“…The FT-IR spectrum (v, cm À 1 ) of compound 4 a was recorded as a KBr tablet, which contains the desired stretching and bending vibrations. In the FT-IR spectrum of this compound NÀ H stretching vibrations were observed at 3427, CÀ O stretching vibrations at 1272-1497, CÀ H stretching vibrations of the aromatic ring at 3070, C=C stretching vibrations of the aromatic ring at 1461-1651, aliphatic CÀ H stretching vibrations at 2930 [47] 4 b 90 298-301 347-349 [47] 4 c 85 248-250 -4 d 88 150-152 295-298 [48] 4 e 92 244-247 264-265 [49] 4 f 88 190-193 335-337 [47] [50] 4 h 80 160-163 176-179 [51] 4 i 80 181-183 -4 j 83 240-242 245-247 [50] 4k 86 198-200 - [52] 4 m 92 190-192 263-265 [50] 4 n 87 207-209 232-234 [53] 4 o 88 193-195 258-261 [54] 4 p 84 270-272 - [55] 4 s 90 225-228 233-235 [56] 4 t 87 216-218 232-233 [57] 4 u 86 280-282 270-272 [58] Messages related to 8 types of hydrogen were observed. NH amino protons appeared in the low field at 13.33 ppm as a small peak with the area under the peak equal to 1 hydrogen.…”