An Investigation into Domino‐Heck Reactions of N‐Acylamino‐Substituted Tricyclic Imides: Synthesis of New Prospective Pharmaceuticals

Heck and domino‐Heck reactions of unsaturated N‐acylamino‐substituted tricyclic imides with aryl(heteroaryl) iodides and phenyl‐ or (trimethylsilyl)acetylene were either carried out in the presence of formate or phenyl‐ and (trimethylsilyl)acetylene, respectively. The C? C coupling reactions appeared to be completely diastereoselective, giving the corresponding N‐acylamino‐5‐exo‐aryl (heteroaryl)‐ ( 5a – c, 6a , b ), N‐(benzoylamino)‐5‐exo‐phenyl‐6‐exo‐[(trimethylsilyl)ethynyl]‐ ( 5d ), or 5‐exo‐(4‐chlorophenyl)‐N‐(2,2‐dimethylpropanoylamino)‐6‐exo‐(phenylethynyl)bicyclo[2.2.1]heptane‐2‐endo,3‐endo‐dicarboximide ( 6c ) (Schemes 3 and 4).     

Spectrophotometric multicomponent determination of sunset yellow, tartrazine and allura red in soft drink powder by double divisor-ratio spectra derivative, inverse least-squares and principal component regression methods

Double divisor-ratio spectra derivative (graphical method), classical least-squares and principal component regression (two numerical methods) methods were developed for the spectrophotometric multicomponent analysis of soft drink powders and synthetic mixtures containing three colorants without any chemical separation. The graphical method is based on the use of derivative signals of the ratio spectra using double divisor. In this method, the linear determination ranges were 2-8 mug ml(-1) sunset yellow, 4-18 mug ml(-1) tartrazine and 2-8 mug ml(-1) allura red in 0.1 M HCl. In the numerical methods, a training set was randomly prepared by using 18 samples containing between 0 and 8 mug ml(-1) of sunset yellow, 0-18 mug ml(-1) of tartrazine and 0-8 mug ml(-1) of allura red. The chemometric calibrations were calculated by using the prepared training set and its absorbances at seven points (from 375.0 to 550.0 nm) in the spectral region 325-584 nm. The proposed methods were validated by using synthetic ternary mixtures and applied to the simultaneous determination of three colorants in soft drink powders. The obtained results were statistically compared with each other.     

Synthesis, characterization and thermoreversible behaviours of poly(dimethyl siloxane)/poly(N-isopropyl acrylamide) semi-interpenetrating networks

Simultaneous and sequential poly(N-isopropyl acrylamide) (PNIPAAm)/poly(dimethyl siloxane) (PDMS) semi-interpenetrating polymer networks (IPNs) with different linear PDMS contents were prepared by free radical polymerization method. Their phase morphologies have been characterized by FTIR, DSC and SEM. The simultaneous semi-IPNs exhibited phase transition temperatures (T_pt) shifted higher temperature from glass transition temperatures (T_g) of their respective homopolymers, suggesting a heterophase morphology and only physical entanglement between the PNIPAAm network and linear PDMS with high molecular weight (Mn≈9000 g/mol). For sequential semi-IPNs, the shift of T_pts towards lower temperature suggested that the chemical interaction between the constituents of the IPNs increased with increasing PDMS content in the network. In addition, these semi-IPNs were characterized for their thermo-sensitive behaviour by equilibrium swelling studies. The results showed that incorporation of hydrophobic PDMS polymer into the thermo- and pH-sensitive PNIPAAm and P(NIPAAm-co-IA) (itaconic acid) hydrogels by semi-IPN formation decreased swelling degrees of IPNs without affecting their LCSTs whereas addition of acrylated PDMS (Tegomer V-Si 2250) as crosslinker instead of N,N^′-methylenebisacrylamide (BIS) into the structures of these hydrogels changed their LCSTs along with their swelling degrees.     

Inkjet Printing of Functional Polymers and Materials: 2nd International Workshop in Eindhoven

This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de.     

Synthesis of palladium complexes derived from imidazolidin‐2‐ylidene ligands and used for catalytic amination reactions

N‐Aryl amination and the Buchwald–Hartwig reaction are of great synthetic and industrial interest and scientists accept their usefulness and versatility for obtaining arylamines. In this study Ag–N‐heterocyclic carbene complexes were used as transmetallation reagents for the synthesis of Pd–N‐heterocyclic carbene complexes. The new Pd–N‐heterocyclic carbene complexes were characterized using elemental analysis and ¹H NMR, ¹³C NMR and infrared spectroscopies. The crystal structure of one, namely dichlorobis[1,3‐bis(2‐methylbenzyl)imidazolidin‐2‐yliden]palladium(II), is presented. The activity of the Pd(II) complexes in the coupling reaction of anilines or amines with bromobenzene was investigated. These complexes exhibited high catalytic activities in the direct synthesis of triarylamines and secondary amines in a single step. Copyright © 2016 John Wiley & Sons, Ltd.     

Synthesis,Spectroscopic, and Dyeing Properties of New Azo and Bisazo Dyes Derived from 5‐Pyrazolones

This study is in continuation of our work related to 5‐pyrazolones aimed at synthesizing new heterocycles with dyeing and anticipated biological properties. Compounds 1 and 2 ; 1‐methyl‐ or 1‐(2,4‐dimethylphenyl)‐3‐phenyl‐1H‐pyrazol‐5(4H)‐one, 3 ; 1‐methyl‐5‐oxo‐3‐phenyl‐4,5‐dihydro‐1H‐pyrazole‐4‐carbaldehyde and 4 ; 2‐(1‐methyl‐5‐oxo‐3‐phenyl‐1H‐pyrazol‐4(5H)‐ylidene)‐3‐phenylthiazolidin‐5‐one were prepared and subjected to diazotation with aromatic amines and diamines. New azo ( 1a – c , 2a, b , 3a , b , 4a , c ) and bisazo dyes ( 2c , d , 4b ) were obtained, and their structures were confirmed by spectroscopic and analytical methods. In addition, UV–vis measurements, dyeing performance, and fastness tests were carried out for all compounds.     

Phase separation behavior of whey protein isolate particle dispersions in the presence of xanthan

In this study, phase separation of colloidal whey protein isolate (WPI) particle dispersions was studied using a rod-like polysaccharide xanthan. Effects of different xanthan concentration, particle volume fraction, and temperature were analyzed by visual observations, turbidity measurements, and particle mobility tracking method. Particle mobility was determined using a diffusing wave spectroscopy (DWS) set up. Xanthan concentration was kept low in order not to increase the viscosity of dispersions, so that the phase separation could be observed easily. Visual observations showed that there was a minimum concentration of xanthan to induce phase separation at a constant particle volume fraction, and xanthan concentration was found to have an important effect on the degree of phase separation. The temperature was also found to have an effect on depletion mechanism. Phase separation was mainly a result of different sizes of WPI particles, and xanthan induced the depletion interaction between WPI particles, as supported by the data obtained from DWS. The results of this study explained both the mechanism and the stability range of particle dispersions in the presence of xanthan, which is important for the design of stable systems, including colloidal particles.     

A numerical study of the semi‐classical limit for three‐coupled long wave–short wave interaction equations

We study numerically the semi‐classical limit for three‐coupled long wave–short wave interaction equations. The Fourier–Galerkin semi‐discretization is proved to be spectrally convergent in an appropriate energy space. We propose a split‐step Fourier method in the semi‐classical regime with the discussion of the meshing strategy, which is necessary to obtain correct numerical solution. Plane wave solution with weak and strong initial phases, solitary wave solution and Gaussian solution are considered to investigate the semi‐classical limit.