Ultrasound- and microwave-assisted synthesis of (E)-1-aryl-3-[2-(piperidin-1-yl)quinolin-3-yl]prop-2-en-1-ones and (E)-1-aryl-3-[2-(pyrrolidin-1-yl)quinolin-3-yl]prop-2-en-1-ones,and their antimicrobial activity

Series of new (E)-1-aryl-3-[2-(piperidin-1-yl)quinolin-3-yl]prop-2-en-1-ones and (E)-1-aryl-3-[2-(pyrrolidin-1-yl)quinolin-3-yl]prop-2-en-1-ones have been efficiently prepared via the Claisen-Schmidt condensation of 2-(piperidin-1-yl)quinoline-3-carbaldehyde and 2-(pyrrolidin-1-yl)quinoline-3-carbaldehyde, respectively, with aryl methyl ketones under conditions of ultrasound and microwave irradiation. Structures of the products have been confirmed by IR, ¹H NMR, ¹³C NMR, and mass spectroscopy, as well as by elemental analysis. Evaluation of the in vitro antibacterial activity against bacterial (Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli) and fungal (Aspergillus niger and Candida metapsilosis) strains has revealed good antimicrobial activity of some of the tested compounds.     

Synthesis and Biological Activity of Cis 2-(6-Chloropyridine-3-yl)methylamino-4-substitutedphenyl-5,5-dimethyl-1,3,2-dioxaphosphinane 2-Oxides

A series of novel, asymmetric-cyclic phosphoramides containing substituted pyridine were synthesized via the condensation reactions of trans 2-chloro-4-substitutedphenyl-5, 5-dimethyl-1,3,2-dioxaphosphinane 2-oxide with 2-chloro-5-aminomethylpyridine or 3-aminomethylpyridine. The reactions show good stereoselectivity. Only the cis isomer from configuration inversion was obtained, which is the thermodynamic stable product. The structures of the products were characterized by ¹H NMR, ³¹P NMR, IR, MS, and elemental analysis. The configuration of the product was determined by X-ray diffraction analysis. The results of preliminary bioassay showed that the new compounds possess potential insecticidal and fungicidal activities.     

Hydrogen Bonds in 2-(Diorganylphosphorylhydroxymethyl)-1-organylimidazoles

Structures of 2-(diorganylphosphorylhydroxymethyl)-1-organylimidazoles were studied by IR and ¹H and ^{3 1}P NMR spectroscopy, and also by ab initio calculations (HF/6-31G*). Formation of intramolecular O-H+++O = P hydrogen bonds in solutions of these compounds in CCl₄ and CHCl₃ was established.     

Synthesis and Biological Activities of O-Alkyl,O-Aryl,O-{Z-[1-Phenyl-2-(1H-1,2,4-triazol-1-yl)ethylidene]amino} Phosphorothioates

A series of title compounds 2 were efficiently synthesized via the condensation of 1-phenyl-2-(1H-1,2,4-triazol-1-yl)ethanone oxime with various asymmetric thiophosphoryl chlorides in sodium hydroxide powder and acetonitrile system. The structures of title compounds 2 were confirmed by IR, ¹H NMR, ³¹P NMR, EI-MS, and elemental analysis. The results of preliminary bioassays indicated that the title compounds 2 possessed good to moderate insecticidal activity against aphides at the dosage of 250 mg/L, and some of them exhibited moderate fungicidal activities at the concentration of 100 mg/L.     

Synthesis,spectral characterization and biological evaluation of novel 1-(2-(4,5-dimethyl-2-phenyl-1H-imidazol-1-yl)ethyl)piperazine derivatives

A simple, highly useful synthesis of 1-(2-(4,5-dimethyl-2-phenyl-1H-imidazol-1-yl)ethyl)piperazine derivatives is achieved by a four component cyclo condensation of diacetyl, aromatic aldehyde, 2-(piperazin-1-yl)ethanamine and ammonium acetate using SO₄²⁻/Y₂O₃ as a catalyst in ethanol. The synthesized compounds were characterized by IR, ¹H and ¹³C NMR and mass spectral studies. All the synthesized compounds were screened for their in vitro antimicrobial studies. Among the newly synthesized compounds 5d, 5e, 5h and 5m showed excellent antibacterial and antifungal activities when compared to the standard drugs.     

Structure and spectral property of 8-(2-(5-(4-methylphenyl)-2-thienyl)vinyl)-10,10-dimethyl-10H-pyrido[1,2-a]indolium perchlorate

The title compound 8-(2-(5-(4-methylphenyl)-2-thienyl)vinyl)l-10,10-dimethyl-10H-pyrido[1,2-a]indolium perchlorate (3) has been synthesized by cycloaddition and condensation reactions, and characterized by elemental analysis, IR, ¹H NMR, and single-crystal X-ray diffraction. The crystal structure analysis exhibits that the molecule of 3 possesses good coplanarity, and the three rings (10H-pyrido[1,2-a]indolium, thienyl and phenyl) and vinyl moiety can make up a large conjugated system. Its UV-Vis and fluorescence spectra were measured, and found that it displays larger maximum absorptions and emission wavelengths in comparison with 8-(4-methylphenyl)vinyl analogue.     

Asymmetric hydrogenation of alkenes with planar chiral 2-phosphino-1-aminoferrocene-iridium(I) complexes

The first highly enantioenriched and enantiopure planar chiral 2-phosphino-1-aminoferrocene ligands and their Ir(COD)BAr_F complexes are reported. The ligands display bidentate coordination behavior towards iridium, as indicated by trends in ³¹P and ¹H NMR spectra of the phosphine moieties and the α to nitrogen substituents of the amines. All of the new complexes showed good reactivity as catalysts in promoting asymmetric hydrogenation of several prochiral alkenes, with enantioselectivities up to 92%. Iridium complexes of dimethylaminoferrocene derivatives containing P-Ar groups [PPh₂ and P(o-tol)₂] gave the highest levels of asymmetric induction.     

A simple synthesis of the pentacyclic lamellarin skeleton from 3-nitro-2-(trifluoromethyl)-2H-chromenes and 1-methyl(benzyl)-3,4-dihydroisoquinolines

The basic structural framework of lamellarin alkaloids, 8,9-dihydro-6H-chromeno[4′,3′:4,5]pyrrolo[2,1-a]isoquinoline derivatives, has been obtained in good yields via Grob synthesis between 3-nitro-2-(trifluoromethyl)-2H-chromenes and 1-methyl-3,4-dihydroisoquinolines in refluxing isobutanol. In the case of 1-benzyl-3,4-dihydroisoquinolines, a dynamic NMR effect was observed in the ¹H and ¹⁹F NMR spectra of the products as a result of restricted rotation about the single bond linking the benzene ring and the heterocyclic system. When the reaction was carried out with 3-nitro-2-(trichloromethyl)-2H-chromenes in toluene at room temperature, only Michael adducts, as a mixture of two diastereomers, were isolated.     

Diastereoselective synthesis of (2S)-2-[(R)-1H-indol-3-yl(phenyl)methyl]-2,3-dihydro-1H-inden-1-one

Double asymmetric induction in Michael reactions has been studied. Enantioselective alkylation of a cyclic ketone (1-indanone) with α-phenyl-nor-gramine was carried out. The relative configuration of (2S^∗)-2-[(R^∗)-1H-indol-3-yl(phenyl)methyl]-2,3-dihydro-1H-inden-1-one was established by X-ray diffraction. The relative configuration of (R^∗,R^∗,S^∗)- and (S^∗,R^∗,S^∗)-2-1H-indol-3-yl(phenyl)methyl]-2,3-dihydro-1H-inden-1-ols was established by ¹H NMR studies.     

Bis (2,4,6-trihalophenoxy) trichlorophosphoranes: Novel condensing reagents for internucleotidic phosphotriester bond formation via active phosphorochloridate intermediates

New types of reagents, bis (2,4,6-trihalophenoxy)trichlorophosphoranes, were very effective as condensing agents for internucleotidic bond formation in the phosphotriester method. The ³¹P NMR study showed that the condensation proceeded via phosphorochloridate intermediates.     

Synthesis and Herbicidal Activities of 2-Methylpropan-2-Aminium Methyl 1-(Substituted Phenoxyacetoxy) Alkylphosphonates

Abstract

A series of 2-methylpropan-2-aminium methyl 1-(substituted phenoxyacetoxy) alkylphosphonates were selectively synthesized by reacting the corresponding dimethyl 1-(substitutedphenoxyacetoxy)alkylphosphonates with an excess of 2-methylpropan-2-amine. All the title compounds were identified by IR, ¹H NMR, and ³¹P NMR, some of them were further analyzed by ¹⁹F NMR and ¹³C NMR. Their herbicidal activity was investigated and the results showed that most of the demethylated aminium salts exhibited notable herbicidal activities against Brassica napus L. and Echinochloa crusgalli.

Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional text, figures and tables.     

Structure and properties of 2-[(E)-2-(4-dipropylaminophenyl)-1-ethenyl]-1,3,3-trimethyl-3H-indolium chloride

The structure of styryl dye, 2-[(E)-2-(4-dipropylaminophenyl)-1-ethenyl]-1,3,3-trimethyl-3H-indolium chloride (I), was investigated using methods such as UV-VIS, fluorescence spectroscopy, and NMR (¹H, ¹³C, APT, HMQC, COSY) and also by examining its electrochemical properties. A study of the acid-base properties revealed the existence of three different forms of the dye. The mechanisms of protolysis and hydrolysis are discussed. The reagent exists in a reactive single-charged form I ⁺ over a wide range of acidity (pH 4–11). The optimum analytical wavelength of the singlecharged form is 550 nm, where the molar absorptivity is 5.51 × 10⁴ L mol^?1 cm^?1. The values of the optimum analytical wavelength and molar absorptivity of the protolysed and hydrolysed forms are: λ _max(I-H²⁺) = 380 nm, ?(I-H²⁺) = 2.01 × 10⁴ L mol^?1 cm^?1; λ _max(I-OH) = 320 nm, ?(I-OH) = 1.12 × 10⁴ L mol^?1 cm^?1. A theoretical study of the spectral and chemical properties of I was carried out by performing quantum chemical calculations.     

P NMR study of the stoichiometry, stability and thermodynamics of new complexation between uranyl (II) nitrate and N-methyliminobis(methylenephosphonic acid) in two binary D2O-DMSO-d6 solvent mixtures

The complexation reaction between uranyl (II) nitrate, and N-methyliminobis(methylenephosphonic acid) (MIDPH) was investigated in two different binary solvent mixtures of D₂O-DMSO-d₆ at various temperatures using ³¹P NMR spectroscopy. The exchange between the free ligand and the 1:1 complexed ligand was slow on the NMR timescale and two ³¹P NMR signals were observed. The formation constant of the resulting complex was evaluated from integration of the two ³¹P NMR signals. The values of thermodynamic parameters of the resulting complex (ΔH, ΔS and ΔG) were determined from the temperature dependence of the formation constants. In the two solvent mixtures studied, the resulting complex is enthalpy stabilized but entropy destabilized.     

Diels-Alder reaction of 2-phosphaindolizines catalysed by organoaluminium reagent: theoretical and experimental results

Theoretical calculations at the DFT (B3LYP/6-31+G^**) level of the model Diels-Alder (DA) reactions of 1-methyl-3-(methoxycarbonyl)-2-phosphaindolizine with 1,3-butadiene in the presence of methylaluminium dichloride reveal that the co-ordination of organoaluminium reagent to the carbonyl oxygen increases the activation barrier compared to that for the uncomplexed 2-phosphaindolizine. On the other hand, co-ordination of the organoaluminium reagent to the σ², λ³ P atom lowers the activation barrier by ∼6 kcal mol⁻¹. 1-Methyl-2-phosphaindolizines having an electron-withdrawing group at the 3-position only undergo DA reaction with 2,3-dimethylbutadiene in the presence of the ethylaluminium dichloride catalyst in methylene chloride at a low temperature to afford [2+4] cycloadducts. The formation of an intermediate having the ethylaluminium reagent co-ordinated to σ², λ³ P atom has been detected by ³¹P NMR. The products have been characterized by ³¹P and ¹H NMR studies.     

Ammonium chloride-catalyzed one-pot synthesis of 3,4-dihydropyrimidin-2-(1H)-ones under solvent-free conditions

Ammonium chloride as a very inexpensive and readily available reagent, and efficiently catalyzes one-pot, three component, Biginelli condensation reactions of aldehydes, 1,3-dicarbonyl compounds and urea or thiourea under solvent-free conditions to afford the corresponding 3,4-dihydropyrimidin-2-(1H)-ones in high yields at 100°C.     

Microwave assisted selective synthesis of (<Emphasis Type="Italic">E</Emphasis>)-1-(4-Chloro-7-hydroxy-2-aryl-2<Emphasis Type="Italic">H</Emphasis>-chromen-6-yl)-3-arylprop-2-en-1-ones and their antimicrobial activity

A series of new (E)-1-(4-chloro-7-hydroxy-2-aryl-2H-chromen-6-yl)-3-arylprop-2-en-1-ones (2a–2f) have been synthesized by selective mono cyclization of 4,6-dicinnamoyl resorcinols (1a–1f) using Vilsmeier–Haack reagent under conventional heating and microwave irradiation. The structures of the synthesized compounds have been elucidated by elemental analysis, IR, ¹H NMR, ¹³C NMR and Mass spectral data. The synthesized compounds were tested in vitro for antimicrobial activity.     

Novel bicyclic hexanuclear copper(I) aggregate: Structure and solid state P CPMAS NMR spectra of [(Cu3L3)2] and [Cu(PPh3)2L] complexes of N-(diisopropoxythiophosphinyl)-N′-phenylthiourea (HL)

A new complex of N-thiophosphorylthiourea PhNHC(S)NHP(S)(OiPr)₂ (HL) of formula [(Cu₃L₃)₂] has been synthesized and characterized by single crystal X-ray diffraction, FT-IR, ¹H, ³¹P NMR in solution and by ³¹P CPMAS NMR spectroscopy in the solid state. A comparison of the structure and the spectral parameters of [(Cu₃L₃)₂] with those of the mononuclear analogue [Cu(PPh₃)₂L] was performed. In the solid state the aggregate [(Cu₃L₃)₂] represents the first example of a spontaneous “side-by-side” association of two neutral cyclic [Cu₃L₃] moieties using two Cu-S-Cu bridges formed by the sulfur atoms of the PS-groups. The values of the ¹J(³¹P-^63,65Cu) and ²J(³¹P-³¹P) coupling constants of the [Cu(PPh₃)₂]⁺ moiety in the solid state spectra are reported.     

An efficient synthesis of dialkyl 2-(diphenoxyphosphoryl)-3-(alkylthio)succinates from alkylthiols, triphenyl phosphite and dialkyl acetylenedicarboxylates

An efficient synthesis of dialkyl 2-(diphenoxyphosphoryl)-3-(alkylthio)succinates, as a mixture of two diastereomers, in 78–90% yields, is described via reaction between alkylthiols, dialkyl acetylenedicarboxylates, and triphenyl phosphite. The structures of products were deduced from their high-field ¹H, ¹³C, and ³¹P NMR spectra, and IR spectral data. Since these hosphonate esters possess two stereogenic centers, two diastereomers with gauche HCCH arrangements are possible. Observation of ³ J _HH = 3.5-4.6 Hz for the vicinal methine protons confirmed the dominance of the gauche arrangement. A mechanism is proposed for the formation of products.     

Synthesis of 5-hydroxy-N-(2-vinyloxyalkyl)indoles from dicarbonyl compounds and vinyloxyalkylamines

N-(Vinyloxyalkyl)enaminoketones were obtained by the condensation of vinyloxyalkylamines with acetylacetone or ethyl acetoacetate. Their subsequent reactions with 1,4-benzoquinone produce the corresponding 5-hydroxy-2-methyl-N-(2-vinyloxyalkyl)indoles in 17–43% yields. The structures of the compounds obtained were confirmed by IR and¹H NMR spectroscopy.     

Facile synthesis of 2-carboxanilido-3-arylquinazolin-4-ones from N1-(2-carboxyphenyl)-N2-(aryl)oxalamides

A simple and efficient approach for the synthesis of novel 2-carboxanilido-3-arylquinazolin-4-ones via the one-pot condensation of readily available N¹-(2-carboxyphenyl)-N²-(aryl)oxalamides with various aromatic amines is described. Notably, this methodology allows us to synthesize 3-aryl-quinazolin-4-ones using aromatic amines with various substituents, both electron-donating and electron-withdrawing, which ensures structural diversity of the products and an atomic-economic process.