Herein, we report a facile synthetic methodology for the preparation of 2,3-dialkylquinolines from anilines and propionaldehydes. This cyclization involved environmentally friendly Nafion® NR50 as an acidic catalyst with microwave irradiation as the heating source. A series of substituted 2-ethyl-3-methylquinolines were prepared from various anilines and propionaldehyde derivatives through this protocol with good to excellent yields. Some new chemical structures were confirmed by X-ray single-crystal diffraction analysis and the related data were provided. The plausible reaction mechanism studies are also discussed.
In this study, six coordination polymers (CPs), {[Ag2(L)(CF3SO3)]·CF3SO3·2H2O·DMF}n (1), {[Ag(L)]·SbF6·4DMF·H2O}n (2), {[Zn(L)0.5(I)2]·3.75H2O}n (3), {[Cd2(L)(I)4(H2O)(DMF)]·4H2O·3DMF}n (4), {[Hg2(L)(I)4]·H2O·4DMF}n (5) and {[Hg2(L)(Cl)4]·2H2O·3DMF}n (6), were obtained based on the designed X-shaped urea-based ligand. X-ray single crystal diffraction analysis revealed that complex 1 displayed a 3D (3,4)-connected {6·82}{64·82}-tcj net. Complex 2 featured a 2D 4-connected {43·63} sheet. Complexes 3 and 5 exhibited a 1D polymeric loop chain. Complex 4 displayed a 1D polymeric fishbone chain. Complex 6 showed a 2D 4-connected {44·62}-sql sheet. Structural comparison revealed that not only the metal ions, but also the anions played crucial roles in the control of final structures.
A series of chiral 10-heteroazatriquinanes were synthesized from enantiopure asymmetric cis-2,5-disubstituted pyrrolidines through a one-pot tandem cyclization procedure. The structures and configurations of these new chiral 10-heteroazatriquinanes are confirmed by X-ray single-crystal diffraction analysis.
A new compound, 2-carboxylbenzaldehyde-2-pyrroleformylhydrazone (C13H11N3O3), was synthesized by condensation of 2-carboxylbenzaldehyde (C8H6O3) with 2-pyrroleformylhydrazine (C5H7N3O). Its structure has been determined on the basis of elemental analysis, FTIR spectrum, UV-vis spectrum,1HNMR,13CNMR, MS and X-ray single-crystal diffraction analysis.
Abstract
Three new metal−organic frameworks based on scandium(III) cations and 2,5-thiophenedicarboxylic acid (H2Tdc) are synthesized: [Sc(Tdc)(OH)]·1.2DMF (I), [Sc(Tdc)(OH)]·2/3DMF (II), and (Me2NH2)[Sc3(Tdc)4(OH)2]·DMF (III) (DMF is N,N-dimethylformamide). The structures of the compounds are determined by single-crystal X-ray structure analysis (CIF file CCDC nos. 2067819 (I), 2067820 (II), and 2067821 (III)). The chemical and phase purity of compound I is proved by elemental analysis, thermogravimetry, X-ray diffraction analysis, and IR spectroscopy.
Starting from trichloro(phenylethyl)silane, six differently fluorinated triaryl(phenylethyl)silanes were synthesized by salt elimination reactions and their structures were determined by X-ray diffraction analysis. Tris(pentafluorophenyl)(phenylethyl)silane reveals a folded structure due to intramolecular π-stacking interactions, while those with a lower degree of fluorination show either intermolecular π-stacking or no interplay between the aryl groups. A similar folded structure was observed for (4-methylphenethyl)tris(pentafluorophenyl)silane and [2-(naphth-2-yl)ethyl]tris(pentafluorophenyl)silane, both generated from the corresponding trichlorosilanes. In contrast, the inversely fluorinated [2-(pentafluorophenyl)ethyl]triphenylsilane only revealed intermolecular π-stacking interactions. Compounds with tetrafluoropyridyl substituents behave differently; with these compounds, π-stacking is only observed between the fluorinated units. All compounds were analyzed by NMR and IR spectroscopy, elemental analyses and single-crystal X-ray diffraction, and found to have strong H/C/N/F···F and N···C contacts.
The crystals of 3-indolepropionic acid have been obtained by evaporation from ethanol solution. The crystal structure of the 3-indolepropionic acid was determined by X-ray single crystal diffraction analysis. The crystal data for 3-indolepropionic acid: monoclinic, space group P2(1)/c, a = 14.3592(8) Å, b = 5.2446(2) Å, c = 12.3518(6) Å, V = 926.96(8) Å3, Z = 4, Mr = 189.21, De = 1.356 g/cm3, T = 298(2) K, F (000) = 400, R = 0.0435 and wR = 0.1010. The compound forms one-dimensional chained structure through hydrogen bonds and π-π interaction.
A aroylhydrazone Schiff-base ligand (1, 4-Bis(2’-formylphenyl)-1,4-dioxabutane isonicotinoylhydrazone) and its Zn (II) complex were synthesized by hydrothermal method. The ligand was characterized by IR spectrum, MS spectrum and X-ray single crystal diffraction analysis. The luminescent properties of the ligand and Zn (II) complex material have been investigated in solid and in organic solvents. The results show that the ligand has strong luminescent emission at ca. 454 nm and the fluorescence of Zn (II) complex is very weak.
Environmentally Friendly Nafion-Catalyzed Synthesis of Substituted 2-Ethyl-3-Methylquinolines from Aniline and Propionaldehyde under Microwave Irradiation