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1.
An efficient and a quick microwave‐assisted synthesis of benzimidazoles and trisubstituted imidazoles was developed. Three benzimidazoles were obtained as a result of the condensation of 1,2‐phenylenediamine with carboxylic acids and acetoacetic ester without catalyst. A series of trisubstituted imidazoles were synthesized by condensation of benzil, aromatic aldehyde and ammonium acetate in the presence of glacial acetic acid. 相似文献
2.
Summary Arylbiguanides2 a–e react with benzoin (1) at thepH of the base to two different products.1 undergoes in presence of the base2 a–e oxidation to benzil and benzoic acid, which reacts fast with the arylbiguanides2 a–e to yield N-[4-(arylamino)-6-phenyl-1,3,5-triazine-2-yl]benzamides3 a–d. After lowering thepH of the reaction mixture, the bases2 b–e react with benzil to yield 2-[1-aryl-5-oxo-4,4-diphenyl-2-imidazoline-2-yl]guanidine4 b–e. The mechanism of the formation is discussed. The structure of4b was established from a single crystal x-ray structure analysis. The analysis was carried out at 100K: C23H21N5O,M
r=383.5, monoclinic, C 2/c,a=15.842(6),b=8.419(3),c=30.223(10) Å, =98.44(3)°,V=3 987.3(9) Å3,Z=8,d
x=1.277 g/cm3, =0.81 cm–1,R=5.89%R
w=4.97% (1 537 observations, 233 parameters). 相似文献
3.
Mohammad Ali Zolfigol Davood Azarifar Iraj Mohammadpoor-Baltork Behrooz Maleki 《Tetrahedron letters》2006,47(5):833-836
4-(p-Chloro)phenyl-1,3,4-triazole-3,5-dione is used as an effective oxidizing agent for the oxidation of 1,3,5-trisubstituted pyrazolines to their corresponding pyrazoles under mild conditions with moderate to good yields at room temperature. 相似文献
4.
Norbert Kuhn Martin Ghner Martin Grathwohl Jrg Wiethoff Gernot Frenking Yu Chen 《无机化学与普通化学杂志》2003,629(5):793-802
2‐Iminoimidazolines — Strong Nitrogen Bases als Ligands in Inorganic Chemistry Due to the tendency of the 5‐membered cyclic fragment to accept a positive charge which yields an ylide type bonding situation, 2‐iminoimidazolines are strong nitrogen bases. They can serve as neutral ligands being 2+2 electron donors. Deprotonation leads to the anions which are potential 2+4 electron donors. We describe first the synthesis and characterization of the title compound 2‐imino‐1, 3‐dimethylimidazoline (ImNH, 8 ) and its anion 9 . Next we demonstrate their properties as ligands in complexes of main group elements and transition metals. In a third chapter we describe attempts to functionalize iminoimidazolines with the goal to create neutral ligands that coordinate in a semistable fashion. On this way we want to make a contribution to the chemistry of complex compounds directed towards catalysis. 相似文献
5.
A one-pot synthesis of the trisubstituted imidazole derivatives from α-acetoxy-α-chloro-β-keto-esters, aldehydes, and ammonium acetate has been developed. 相似文献
6.
Kunchala Dhanunjayarao Shreenibasa Sa Basava Punna Rao Aradhyula Krishnan Venkatasubbaiah 《Tetrahedron》2018,74(40):5819-5825
The synthesis of N,C-coordinated organoboron compounds (B1-B4) based on phenanthroimidazole described. All the compounds were characterized by various spectroscopic techniques. Single crystal X-ray diffraction analysis of the compounds B1 and B3 revealed that the vicinity around the boron atom adopts tetrahedral geometry. Except compound B4, other organoboron compounds (B1-B3) does not show solvatochromism. All our newly synthesized organoboron compounds exhibited moderate to good solution state quantum yields (0.07–0.88) and moderate solid state quantum yields. 相似文献
7.
Hanan Al-Awadi Maher R. Ibrahim Nouria A. Al-Awadi Yehia A. Ibrahim 《Tetrahedron》2007,63(52):12948-12953
Gas-phase thermolysis of thieno[2,3-e][1,2,4]triazines gave benzonitrile, isothiazole, pyridazine, and thieno[2,3-d]thiazole derivatives. Similar transformation of benzo[1,2,4]triazine and phenanthro[9,10-e][1,2,4]triazine derivatives into their corresponding condensed thiazoles has been achieved by heating at 350 °C with sulfur. A mechanism for these pyrolytic transformations was proposed. 相似文献
8.
Substituted imidazoles and purine bioisosteres have been widely studied in the literature. We endeavored to combine these heterocyclic core structures into precursors, especially 7-azaindoles, of previously unknown pharmacologically relevant lead structures. A highly flexible synthetic procedure was developed, derived from investigations of the influence of the substrates, solvents, ligand systems, and side reactions. 相似文献
9.
10.
The reactivity of stereochemically defined 3-aryl-2-chloro-2-imidoylaziridines, an unexplored class of substituted aziridines, was investigated under various reaction conditions. 2-Chloro-2-imidoylaziridines underwent a novel thermal rearrangement by reflux in acetonitrile via C-C bond cleavage to 4-chloro-2,5-diarylimidazoles in high yield. Alternatively, a novel efficient entry toward 2-aroyl-2-chloroaziridines was based on the chemoselective hydrolysis of 2-chloro-2-imidoylaziridines with hydrochloric acid in aqueous tetrahydrofuran. 相似文献