Efficient One‐Pot Synthesis of Bis(4‐hydroxycoumarin)methanes in the Presence of Sulfonic Acid Functionalized Nanoporous Silica (SBA‐Pr‐SO3H)

An efficient and simple method for the synthesis of bis(4‐hydroxycoumarin)methanes has been achieved through a one‐pot condensation of aryl aldehydes and 4‐hydroxycoumarin in the presence of nanoporous solid acid catalyst of SBA‐Pr‐SO₃H with pore size of 6 nm. Excellent yields, short reaction times, reusability of the catalyst and simple workup are advantages of this synthetic procedure.     

Conductometric study of complexation reaction of 4′-nitrobenzo-15-crown-5 with Mn+2, Co+2, Y+3, and ZrO+2 cations in acetonitrile,methanol and their binary solvent solutions

The complexation reactions of Mn²⁺, Co²⁺, Y³⁺, and ZrO²⁺ cations with the macrocyclic ligand, 4′-nitrobenz-15-crown-5 (4′-NB15C5), in acetonitrile (AN), methanol and AN-MeOH binary mixtures have been studied at various temperatures using the conductometric method. The conductance data stand for the Me : L stoichiometric ratio 1 : 1. Values of the formation constants of the complexes were accumulated by plotting molar conductivity curves using the computer program, GENPLOT. The order of stability of the metal-ion complexes in pure AN at 15°C was found to be: (4′-NB15C5 · ZrO)²⁺ > (4′-NB15C5 · Mn)²⁺ ≈ (4′-NB15C5 · Co)²⁺ > (4′-NB15C5 · Y)³⁺. In the case of AN-MeOH binary solvent solutions with 50 and 75 mole percent of AN at the same temperature, the sequence of stability of the complexes was the following: (4′-NB15C5 · Mn)²⁺ > (4′-NB15C5 · ZrO)²⁺ ≈ (4′-NB15C5 · Co)²⁺ 〉 (4′-NB15C5 · Y)³⁺, and (4′-NB15C5 · Mn)²⁺ > (4′-NB15C5 · Y)³⁺ ≈ (4′-NB15C5 · Co)²⁺ > (4′-NB15C5 · ZrO)²⁺, respectively. The complexes formed are entropy stabilized in all cases.     

Water-Soluble Rhenium Clusters with Triazoles: The Effect of Chemical Structure on Cellular Internalization and the DNA Binding of the Complexes

Here we explore the effect of the nature of organic ligands in rhenium cluster complexes [Re₆Q₈L₆]⁴⁻ (where Q=S or Se, and L=benzotriazole, 1,2,3-triazole or 1,2,4-triazole) on the biological properties of the complexes, in particular on the cellular toxicity, cellular internalization and localization. Specifically, the study describes the synthesis and detailed characterization of the structure, luminescence and electrochemical properties of the four new Re₆ clusters with 1,2,3- and 1,2,4-triazoles. Biological assays of these complexes are also discussed in addition to those with benzotriazole using cervical cancer (HeLa) and immortalized human fibroblasts (CRL-4025) as model cell lines. Our study demonstrates that the presence of hydrophobic and π-bonding rich units such as the benzene ring in benzotriazole significantly enhances cellular internalization of rhenium clusters. These ligands facilitate binding of the clusters to DNA, which results in increased cytotoxicity of the complexes.     

Inside-tube solid-phase microextraction as an interlink between solid-phase microextraction and needle device for n-hexane evaluation in air and urine headspace

Monitoring the trace amount of chemicals in various samples remains a challenge. This study was conducted to develop a new solid-phase microextraction (SPME) system (inside-tube SPME) for trace analysis of n-hexane in air and urine matrix. The inside-tube SPME system was prepared based on the phase separation technique. A mixture of carbon aerogel and polystyrene was loaded inside the needle using methanol as the anti-solvent. The air matrix of n-hexane was prepared in a Tedlar bag, and n-hexane vapor was sampled at a flow rate of 0.1 L/min. Urine samples spiked with n-hexane were used to simulate the sampling method. The limit of detection using the inside-tube SPME was 0.0003 μg/sample with 2.5 mg of adsorbent, whereas that using the packed needle was 0.004 μg/sample with 5 mg of carbon aerogel. For n-hexane analysis, the day-to-day and within-day coefficient variation were lower than 1.37%, with recoveries over 98.41% achieved. The inside-tube SPME is an inter-link device between two sample preparation methods, namely, a needle trap device and an SPME system. The result of this study suggested the use of the inside-tube SPME containing carbon aerogel (adsorbent) as a simple and fast method with low cost for n-hexane evaluation.     

Polarization-Dependent Mode Analyzer and Controlled-Z Gate in Ti:LiNbO3 Quantum Photonic Circuits

Abstract

On-chip integrated photonic circuits are crucial for further progress toward quantum technologies and in the science of quantum optics. The quantum controlled-Z gate is an example of the maximally entangling gate, which is universal for quantum computing when coupled with single-qubit gates. This article demonstrates a deterministic controlled-Z photonic quantum gate based on titanium in-diffused channel waveguides in which polarization and modal degrees of freedom of a single photon are used for encoding the control and target qubits, respectively.     

Synthesis,Characterization and Crystal Structures of new 1,2,4‐Triazole based Schiff‐bases and their Copper(I) Complexes

The reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (AMTT, 1 ) with 4‐methoxy benzaldehyde and 3‐methoxybenzaldehyde in methanol led to the iminic derivatives 4‐(4‐methoxybenzylideneamino)‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)thione ( 2 , L1) and 4‐(3‐methoxybenzylideneamino)‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione ( 3 , L2). The reaction of the latter with [(PPh₃)₂CuCl] in methanol solution gave the first Cu^I complex of 3 , [(PPh₃)₂CuCl(L2)] ( 4 ) and in chloroform solution the complex [(PPh₃)₂CuCl(L2)]·2CHCl₃ ( 5 ). All compounds were characterized by infrared spectroscopy, elemental analyses as well as by X‐ray diffraction studies. Crystal data for 2 at ?80 °C: space group P2₁/c with a = 1351.3(3), b = 399.4(1), c = 2225.2(5) pm, β = 96.50(2)°, Z = 4, R₁ = 0.0667, for 3 at ?80 °C: space group R3c with a = b = 3020.4(2), c = 708.2(1) pm, Z = 18, R₁ = 0.0435, for 4 at ?80 °C: space group P2₁/c with a = 1427.8(1), b = 1129.0(1), c = 2622.8(2) pm, β = 97.19(1)°, Z = 4, R₁ = 0.0517 and for 5 at ?80 °C: space group with a = 1280.5(1), b = 1316.1(1), c = 1731.4(1) pm, α = 78.14(1)°, β = 86.06(1)°, γ = 64.69(1)°, Z = 2, R₁ = 0.0525.     

Preparation of Magnetic Molecularly Imprinted Polymer Nanoparticles for Selective Adsorption and Separation of β-Estradiol

In this study, we report the synthesis of MIP-coated hybrid NPs by “semi-covalent” imprinting technique throught a thermally reversible covalent bond and application for biochemical separation of β-estradiol (E₂). A moleculary imprinted polymer (MIP) were synthesized using 3-(triethoxysilyl) propyl isocyanate and dibutyltin dilanurate as a functional monomer and cross-linking agent and β-estradiol as template. The removal of the template by a simple thermal reaction produced specific β-estradiol recognition sites on the surface of silica shell. Meanwhile, a solid-phase extraction (SPE) based on E₂- MMIPs has been established for efficient separation and fast enrichment of E₂ from the plasma. Recoveries of E₂ from two kinds of plasma spiked at different concentration levels ranged from 86.9 to 103.3 with RSD <1.76 %.In this manner LOD was 0.0019 and LOQ was 0.0057 (µmol L^?1), capacity factor and selectivity factor were 3.05 and 1.099 respectively. Also E₂- MMIPs was used for selective separation of E₂ from drugs mixture.     

Synthesis and characterization of Si-Zr-Mo nanocomposite as a rapid and efficient catalyst for aromatization of Hantzsch 1,4-dihydropyridines

Nanocomposite of Silica-zirconia-molybdate designated as Si-Zr-Mo was prepared via the reaction of the in situ generated zirconium-tetra octanoxide [Zr(Oct)₄] through condensation of zirconium-tetra-n-butoxide and 1-octanol in a sol–gel method with sulfuric acid and tetraethylorthosilicate (TEOS) followed by grafting of MoO₄^2? on modified silico zirconia nanocomposite under reflux conditions. The prepared nanocomposite was characterized using inductively coupled plasma (ICP), N₂ sorption isotherms, transmission electron microscopy (TEM), and FT-IR spectroscopy. The as prepared nanocomposite had a surface area and pore dimension of 140 m²/g and 1.48 nm, respectively. The morphology of sulphated silico zirconia nanocomposite after immobilization MoO₄^2? has been changed from nanoparticles to nanaorods. It was found that the synthesized nanocomposite successfully catalyze the oxidative dehydrogenation of 1,4-dihydropyridines (1,4-DHPs) with 92–100% conversion and 80–100% selectivity toward the desired products.     

Synthesis,Characterization of a Novel 1,2,4‐Thiotriazine Derivative (CAMTTO), and Copper(I) and Silver(I) Complexes thereof (CAMTTO = {(4‐[(4‐Chlorobenzylidene)‐amino]‐6‐methyl‐3‐thioxo‐[1,2,4]‐triazin‐3,4‐dihydro(2H)‐5‐one)}

The reaction of 4‐amino‐6‐methyl‐1,2,4‐triazin‐thione‐5‐one (H₂AMTTO, 1 ) with 4‐chlorobenzaldhyde led to the corresponding iminic compound {(4‐[(4‐chloro‐benzylidene)‐amino]‐6‐methyl‐3‐thioxo[1,2,4]‐triazin‐3,4‐dihydro(2H)‐5‐one), CAMTTO ( 2 ). Treatment of 2 with copper(I) chloride in chloroform gave the dimeric complex [{(CAMTTO)₂CuCl}₂]·2CHCl₃ ( 3 ). Treatment of 2 with copper(I) chloride and silver(I) nitrate in the presence of the co‐ligand triphenylphophane gave the complexes [(CAMTTO)CuCl(PPh₃)₂] ( 4 ) and [(CAMTTO)Ag(PPh₃)₂]NO₃·2CHCl₃ ( 5 ). All compounds have been characterized by elemental analyses, ¹H NMR spectroscopy, IR spectroscopy, and partly by mass spectrometry and X‐ray diffraction studies. In addition 4 and 5 have been characterized by ³¹P{¹H} NMR spectroscopy. Crystal data for 2 at ?80 °C: monoclinic, space group P2₁/c, a = 1370.3(1), b = 767.8(1), c = 1268.7(1) pm, β = 107.12(1)°, Z = 4, R₁ = 0.0379; for 3 at ?80 °C: monoclinic, space group P2₁/c, a = 1442.6(2), b = 878.8(1), c = 2558.7(3) pm, β = 95.31(1)°, Z = 2, R₁ = 0.0746; for 4 at ?80 °C: triclinic, space group , a = 1287.9(1), b = 1291.7(1), c = 1359.5(1) pm, α = 90.44(1)°, β = 94.81(1)°, γ = 107.54(1)°, Z = 2, R₁ = 0.0359 and for 5 at ?80 °C: triclinic, space group , a = 1060.5(1), b = 1578.2(2), c = 1689.6(2) pm, α = 87.70(1)°, β = 86.66(1)°, γ = 76.84(1)°, Z = 2, R₁ = 0.0487.