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UV irradiation of solutions of the (E)-isomers of five (out of the possible six) monopyridyl analogues at reduced temperatures results in extensive (80-90percent) conversion into the corresponding (Z)-isomers.The process is reversible both thermally and photochemically.The (Z)-isomers are stable at temperatures below -80 deg, and their absorption spectra were estimated.Biacetyl-photosensitized (E)->(Z) isomerization was observed, with (Z)-contents of ca. 70percent at the photostationary state.

Ruthenium(ii) pyridylimine complexes are explored for their potential as units that might be incorporated into electronic or photonic arrays. The complexes [Ru(bipy)2(L)][PF6]2 (1) and [Ru(tpy)(L)Cl][BF4] (2) wi

Heterocyclic imines provide biaryl products by a two-step transformation. The first transformation involves a Diels–Alder reaction with a multiply protonated imine to give a tetrahydroquinoline product, whereas the second step involves oxidation with elem

A novel protocol for the regio- and stereoselective iodofluorination of internal and terminal alkynes using 1,3-diiodo-5,5,-dimethylhydantoin and HF-based reagents is disclosed. This approach is used to prepare a fluorinated tamoxifen derivative in two steps from commercially available starting materials. A facile method enabling controlled regioselective double iodofluorination of terminal alkynes is also presented.

Diels-Alder reactions have been accomplished with ethylene as the dienophile through the use of inverse-electron demand Diels-Alder chemistry. As a key aspect of the chemistry, the dienes are part of tri- or dicationic superelectrophilic systems. Theoreti

Palladium(II) complexes, LnPdCl2 (Ln = LA–LI), with N,N′-bidentate imine ligands derived from picolinaldehyde and substituted anilines have been synthesized and structurally characterized. Molecular structures revealed a distorted square plane geometry around Pd(II) centre in LnPdCl2 (Ln = LA–LC) obtained via coordination with pyridine and imine nitrogens and two chloro ligands. Pd(II) complexes LnPdCl2 (Ln = LA–LI) initiate polymerisation of methylmethacrylate (MMA) in the presence of modified methylaluminoxane (MMAO). The complex LIPdCl2 (of which the ligand was N-furfuryl substituted) showed the highest catalytic activity for the polymerisation of MMA with an activity of 7.08 × 104 g PMMA/mol·Pd·h at 60 °C. All the complexes yielded syndio-rich poly(methyl methacrylate) (PMMA) ([rr] = 0.70). Notably, the substituents on the imine moiety of the iminopyridine fragments affects the activities towards MMA polymerization, whereas the stereoselectivities remained unchanged.

Fifteen new silver(I)-pyridinyl complexes of the general formula [AgL2]X, where X = ClO4?, OTf or NO3?, were synthesised by reacting (E)-N-(pyridinylmethylene)aniline ligands and the respective silver

Reactions of AgO2C2F3with 2-pyridinyl Schiff base ligands bore five novel complexes of the type [(AgO2C2F3)2.L2]: where L?=?L1, (E)-N-(1-(pyridin-2-yl)ethylidene)anili

Several organic soluble N-based ligands and their copper complexes were firstly investigated as catalysts to depolymerise organosolv lignin in the organic solvent, dimethylformamide (DMF) and an ionic liquid (1-ethyl-3-methylimidazolium xylenesulfonate, [

Pyridine complex of zirconium having general formula (I): ? Said pyridine complex of zirconium having general formula (I) may advantageously be used in a catalytic system for the (co)polymerization of conjugated dienes.

From two series of Schiff base ligands, (E)-N-(pyridine-2-yl)(CMe=NPhR) and (E)-N-(pyridine-2-yl)(CH=NPhR) [R = H, L1a, L1b; 2-CH3, L2a, L2b; 4-CH3, L3a, L3b; 2,6-(CH3)2, L4a, L4b; 2,6-(C2H5/sub

A new, single-mode bench-top resonator was evaluated for the microwave-assisted flow generation of primary ketenes by thermal decomposition of α-diazoketones at high temperature. A number of amides and β-lactams were obtained by ketene generation in situ and reaction with amines and imines, respectively, in good to excellent yields. The preferential formation of trans-configured β-lactams was observed during the [2+2] Staudinger cycloaddition of a range of ketenes with different imines under controlled reaction conditions. Some insights into the mechanism of this reaction at high temperature are reported, and a new web-based molecular viewer, which takes advantage from Augmented Reality (AR) technology, is also described for a faster interpretation of computed data.

A series of 12 new cadmium compounds, [Cd(X2)(L)] (4, 10), [Cd(X2)(L)(DMSO)] (9), [Cd(X2)(L)]2 (1-3, 5, 7, 8, 11, and 12), and [Cd(Cl2)2(L)]n (6) where X = chloride, bromide, and

We report the preparation, crystal structure, electrochemistry, and emission properties of Ir(CC:)3, where CC: is an N-heterocyclic carbene ligand. Two synthetic approaches are introduced for generating Ir(iii) complexes bearing imidazolium-bas

Diverse N-substituted anilines bearing hetaryl fragments were easily prepared from corresponding aldimines derived from commercially available aromatic aldehydes and anilines. 2-Furyl substituted anilines showed very good antifungal activities against dermatophytes, particularly against Trichophyton rubrum (MIC = 3.12-6.25 μg/mL). In addition, all active compounds, 45-47, 73, and 74, were tested for cytotoxic activities against breast (MCF-7), lung (H-460), and central nervous system (SF-268) human cancer cell lines with the NCI-anticancer-drug screen. The activity of amines described in this paper, along with the low toxicity of most of them, shows promise for the future development of non-toxic new antimycotic agents.

In spite of the importance of ligand/ copper-catalyzed arylations of nucleophiles in organic chemistry, the structural and electronic features that make a ligand efficient in these reactions have not been determined until now. In this work, several bident

(Chemical Equation Presented) Aldimines derived from aryl and non-enolizable aliphatic aldehydes were allylated with allyl bromide mediated by indium powder in [bpy][BF4] (bpy = N-butylpyridine) to give good yields of the corresponding homoallylic amines. Selective formation of monoallylated amines can be achieved by varying the amount of bromide ion additive in the form of [bpy][Br]. The transient organoindium intermediates, allylindium-(I) and allylindium(III) dibromide formed in the reaction, were studied by NMR spectroscopy to explain the selectivity.

Aziridines carrying three (or two) heteroaryl groups with electron-withdrawing effects were synthesised with sufficient diastereoselectivity. The cis aziridines are susceptible to ring opening and rearrangement when the formation of secondary enamines in

Herein, we quantify how imine exchange may be used to selectively transform one metalloorganic structure into another. A series of imine exchange reactions were studied, involving a set of 4-substituted anilines, their 2-pyridylimines and 1,10-phenanthrolyl-2,9-diimines, as well as the copper complexes of these imine ligands. Electron-rich anilines were found to displace electron-poor anilines in all cases. Linear free energy relationships (LFERs) were discovered connecting the electron-donating or -withdrawing character of the 4-substituent of an aniline, as measured by the Hammett σpara parameter, to that aniline's ability to compete with unsubstituted aniline to form imines. The quality of these LFERs allowed for quantitative predictions: to obtain the desired degree of selectivity in an imine exchange between anilines A and B, the required σpara differential could be predicted using a variant of the Hammett equation, log(KAB) = ρ(σA - σB). We validated this methodology by designing and executing a three-step transformation of a series of copper(I)-containing structures. Each step proceeded in predictably high yield, as calculated from σ differentials. At each step in the series of transformations, macrocyclic structures could be created or destroyed through the selection of mono- or di-amines as subcomponents. The same methodology could be used to predict the formation of a diverse dynamic library of helicates from a set of four aniline precursors, as well as the collapse of this library into one helicate upon the addition of a fifth aniline.

The complete 1H, 13C and 15N NMR analyses for a series of 25 diaryl-aldimines containing phenyl, pyridyl, pyrazolone and furanyl moieties are described herein. Detailed evaluation of substituent chemical shift and coupling constant effects showed that interaction between the lone pair of the pyrazolone carbonyl group or the nitrogen of 2-substitued pyridines with the aldimine hydrogen increases the 1JCH value and shifts the resonance signal for this hydrogen to high frequency, in the 1H NMR spectra. The X-ray crystal structure analysis of pyrazolone substituted aldimines evidenced the planarity of the aryl groups which are conjugated with the C=N double bond. In the case of the N-(2-pyridinemethylene)-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one, two rotamers were observed in the same unit cell.

Five platinum pyridin-2-ylcarboxaldimine complexes of the type cis-[PtCl2(2-C5H4NCH=NR)] (R = CH2CH2OH (1); R = N(CH2CH2)2O (2); R = C6H5 (3); R