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201.
202.
1-(Alkylamino)-2,4-diarylpyrimido[6,1-a]isoquinolin-5-ium chlorides are obtained in good yields via a tandem reaction between isoquinoline, N-alkyl-benzimidoyl chlorides and alkyl isocyanides in anhydrous acetonitrile. 相似文献
203.
Morteza Tahmasebi Masoud Mirzaei Hossein Eshtiagh-Hosseini Joel T. Mague Antonio Bauz Antonio Frontera 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(4):469-477
A new inorganic–organic hybrid based on an aspartate functionalized polyoxomolybdate, [pentaaquacobalt(II)]‐μ‐aspartate‐[γ‐octamolybdate]‐μ‐aspartate‐[pentaaquacobalt(II)] tetrahydrate, [Co2(C4H6NO4)2(γ‐Mo8O26)(H2O)10]·4H2O ( 1 ), has been synthesized under hydrothermal conditions from the reaction of an Evans–Showell‐type polyoxometalate, (NH4)6[Co2Mo10H4O38], and l ‐aspartic acid. The complex exhibits a supramolecular three‐dimensional framework structure in the crystal lattice. Compound 1 was structurally characterized by elemental analyses, IR and UV–Vis (diffuse reflectance) spectroscopy and single‐crystal X‐ray diffraction. In this compound, aspartic acid acts as a bridge between the two Co atoms and the Mo centres, with the –CH2COOH side chain directly linked to the Mo centre in γ‐[Mo8O26]4? and the α‐carboxylate side chain bound to the Co centre. Commonly, the binding of transition‐metal complexes to POMs involves coordination of the metal to a terminal O atom of the POM so that 1 , with a bridging ligand between Mo and Co atoms, belongs to a separate class of hybrid materials. While the starting materials are both chiral and one might expect them to form a chiral hybrid, the decomposition of the chiral Evans–Showell‐type POM and its conversion to the centrosymmetric γ‐octamolybdate POM, plus the presence of two aspartate ligands centrosymmetrically placed on either side of the POM, leads to the formation of an achiral hybrid. We have studied energetically by means of density functional theory (DFT) calculations and using the Bader's `atoms‐in‐molecules' analysis the electrostatically enhanced hydrogen bonds (EEHBs) observed in the solid state of 1 , which are crucial for the formation of one‐dimensional supramolecular assemblies. 相似文献
204.
A catalyst-free and convenient protocol is described for the preparation of 3-aminoimidazo[1,2-a]pyridines and 5-aminoimidazo[2,1-b][1,3]thiazoles via three-component reactions between 2-aminopyridines or 2-aminothiazoles, aldehydes, and isocyanides in water in good to excellent yields. 相似文献
205.
Atom transfer radical polymerization of (meth)acrylates and their novel block copolymers with vinyl acetate 总被引:1,自引:0,他引:1
Mohammad Ali Semsarzadeh Ahmad Mirzaei Ebrahim Vasheghani-Farahani 《European Polymer Journal》2003,39(11):2193-2201
Homopolymerization of methyl acrylate (MA) and methyl methacrylate (MMA) by atom transfer radical polymerization (ATRP) were carried out at 90 °C using methyl-2-bromopropionate (MBP) as initiator, copper halide (CuX, X=Cl, Br) as catalyst, 2,2′-bipyridine (bpy) or N,N,N′,N′,N″-pentamethyldiethylenetriamine (PMDETA) as ligand in 1-butanol (less polar and containing OH) and acetonitrile (more polar) solvents. It was found that with CuCl/bpy catalyst ATRP of MA and MMA in 1-butanol proceeded faster than that in acetonitrile. The rate of ATRP of MA and MMA in acetonitrile and 1-butanol was comparable when CuCl/PMDETA used as catalyst system. The number-average molecular weights increased with conversion and polydispersities were low . The ATRP of MA and MMA with vinyl acetate telomer having trichloromethyl end group (PVAc-CCl3) were also used to synthesize new block copolymers. The structures and molecular weight of synthesized PVAc-b-PMA and PVAc-b-PMMA were characterized by 1H NMR, FTIR spectroscopy and gel permeation chromatography (GPC) and shown that the block copolymers were novel. 相似文献
206.
Ali Sharifi Rahman Hosseinzadeh Mojtaba Mirzaei 《Monatshefte für Chemie / Chemical Monthly》2002,275(2):329-332
The palladium-catalyzed coupling reaction of aryl bromides with various amines under microwave irradiation was studied using PdCl2 [P(o-tolyl)3]2 which gave various aryl amines in good yields. The reactions were carried out under normal atmospheric conditions. 相似文献
207.
1,2,4-triazole was alkylated (alkyl = methyl, butyl, heptyl, decyl) at N-1 in >90% isolated yields. The resulting 1-alkyl triazoles were quaternized at N-4 in >98% isolated yields using fluorinated alkyl halides with >98% isolated yields, under neat reaction conditions at 100-120 degrees C to form N1-CH(3)-N4-(CH(2))(2)C(m)F(2)(m)(+ 1)-triazolium (Taz) iodide (m = 1, 6), N1-C(4)H(9)-N4-(CH(2))(2)C(m)F(2)(m)(+ 1)-Taz iodide (m = 1, 4, 6), N1-C(7)H(15)-N4-(CH(2))(2)C(m)F(2)(m)(+ 1)-Taz iodide (m = 1, 4, 6), N1-C(10)H(21)-N4-(CH(2))(2)C(m)F(2)(m)(+1)-Taz iodide (m = 1, 4), and N1-C(n)H(2)(n )(+ 1)-N4-(CH(2))(2)F-Taz bromide (n = 4, 7, 10). Single-crystal X-ray analyses confirmed the structure of [1-CH(3)-4-CH(2)CH(2)CF(3)-Taz](+)I(-). It crystallized in the orthorhombic space group Pccn, and the unit cell dimensions were a = 13.8289(9) A, b = 17.3603(11) A, c = 9.0587(6) A (alpha = beta = gamma = 90 degrees ). Metathesis of these polyfluoroalkyl-substituted triazolium halides with other salts led to the formation of quaternary compounds, some of which comprise ionic liquids, namely, [R(R(f))-Taz](+)Y(-) (Y = NTf(2), BF(4), PF(6), and OTf), in good isolated yields without the need for further purification: N1-CH(3)-N4-(CH(2))(2)C(m)F(2)(m)( +) (1)-Taz Y (m = 1, 6; Y = NTf(2)), N1-C(4)H(9)-N4-(CH(2))(2)C(m)F(2)(m)(+ 1)-Taz Y (m = 1, 4, 6; Y = NTf(2)), N1- C(7)H(15)-N4-(CH(2))(2)C(m)F(2)(m)(+ 1)-Taz Y (m = 1, 4, 6; Y = NTf(2)), N1-C(10)H(21)-N4-(CH(2))(2)C(m)F(2)(m)(+1)-Taz Y (n = 1, 4; Y = NTf(2)), N1-C(n)H(2)(n )(+ 1)-N4-(CH(2))(2)F-Taz Y (n = 7, 10; Y = NTf(2)), N1-C(10)H(21)-N4-(CH(2))(2)F-TazY (Y = OTf), N1-C(7)H(15)-N4-(CH(2))(2)F-TazY (Y = BF(4)), N1-C(4)H(9)-N4-(CH(2))(2)C(m)F(2)(m) (+ 1)-Taz Y (m = 4, 6; Y = PF(6)), N1-C(7)H(15)-N4-(CH(2))(2)C(4)F(9)-Taz Y (Y = PF(6)), N1-C(4)H(9)-N4-(CH(2))(2)C(m)F(2)(m)(+ 1)-Taz Y (m = 4, 6; Y = OTf). All new compounds were characterized by (1)H, (19)F, and (13)C NMR and MS spectra and elemental analyses. T(g)s and T(m)s of ionic liquids were determined by DSC. 相似文献
208.
Butane sulfobetaines 2a,b, zwitterionic oxo perfluorocarboxylates 3a,b, and functionalized triazolium bromides 4b,c and 5a-c have been synthesized and subsequently reacted to give a series of hydrophilic and hydrophobic fluorinated and nonfluorinated N-1-alkyl-N-4-functionalized-triazolium compounds (6a-11b). With the exception of 11b (mp 41 degrees C), all are liquids at room temperature. Metathesis of the fluorinated quaternary triazolium halides with other anions led to the formation of a new class of compounds, namely, [(R)(R(funct))-Taz](+)Y(-), Y = PF(6), (CF(3)SO(2))( 2)N, and CF(3)SO(3), in good isolated yields. All of the new compounds were characterized by (1)H, (19)F, and (13)C NMR, and MS spectral and elemental analyses. Thermal analyses indicate that high temperatures are attainable prior to decomposition. DSC studies show glass transitions for several samples, and all functionalized compounds, 5-11, have T(g)s or T(m)s <100 degrees C. Densities range between 1.4 and 1.61 g cm(-)(3). 1-Heptyl-4-(butyl-4-sulfonic acid) triazolium trifluoromethanesulfonate, 6b, in its role as a Br?nsted acid, is an effective solvent/catalyst for high yield esterification and hetero-Michael addition reactions and may be recycled for repetitive use. 相似文献
209.
Alkyl and Aryl Complexes of Iridium and Rhodium. XIX. Reaction of Carboxylic Acids with Selected Organo Compounds of Ir(I) and Rh(I): Formation of Arylhydrido, Carboxylatohydrido, and Carboxylato Derivatives cis-Arylhydridoiridium(III) complexes IrH(Ar)(O2CR)(CO)(PPh3)2 (R = Me: Ar = C6H5, 4-MeC6H4; R = Et: Ar = 4-MeC6H4, 2,4-Me2C6H3) could be prepared by oxidative addition of carboxylic acids to aryliridium(I) compounds Ir(Ar)(CO)(PPh3)2. Reaction of aliphatic carboxylic acids with alkyliridium(I) derivatives Ir(Alk)(CO)(PPh3)2 and Ir(Alk)[PhP(CH2CH2CH2PPh2)2] (Alk = CH2CMe3, CH2SiMe3) lead to dicarboxylatoiridium(III) hydrides IrH(O2CR)2(CO)(PPh3)2 (R = Me, Et, i-Pr) and IrH(O2CR)2[PhP(CH2CH2CH2PPh2)2] (R = Me, Et). Ir(4-MeC6H4CO2)(CO)(PPh3)2 was obtained from Ir(CH2SiMe3)(CO)(PPh3)2 and 4-MeC6H4CO2H. Interaction of organorhodium complexes Rh(R′)(CO)(PPh3)2 (R′ = CH2SiMe3, 4-MeC6H4) and Rh(R′)[PhP(CH2CH2CH2PPh2)2] (R′ = CH2CMe3, 4-MeC6H4) with aliphatic and aromatic carboxylic acids yielded carboxylatorhodium(I) compounds Rh(O2CR)(CO)(PPh3)2 (R = Me, t-Bu, 4-MeC6H4) and Rh(O2CR)[PhP(CH2CH2CH2PPh2)2] (R = Me, 4-MeC6H4). 相似文献
210.
Treatment of [Fe(bipy)Cl4][bipy · H] (1) and [Fe(phen)Cl4][phen · H] (3) (where bipy is 2,2′-bipyridine and phen is 1,10-phenanthroline) with dimethyl sulfoxide in methanolic solution produced [Fe(bipy)Cl3(DMSO)] (2) and [Fe(phen)Cl3(DMSO)] (4) (where DMSO is dimethyl sulfoxide), respectively. The resulting complexes were characterized by elemental analysis, IR, UV–Vis and 1H NMR spectroscopies and by the X-ray diffraction method. These complexes are high spin with a spin multiplicity of 6. 相似文献