Corrigendum to: Synthesis and Characterization of a New Group of Exo-Coordinating O2N2-Donor Macrocycles

2018 ◽  
Vol 71 (3) ◽  
pp. 200
Author(s):  
Bahram Ghanbari ◽  
Barzin Safarkoopayeh (Agheli) ◽  
Reze Kia ◽  
Paul R. Raithby

The reaction of 15–18 membered benzodiazacrown ethers with salicylaldehyde afforded n-membered O2N2-donor macrocyclic ligands mounted with 1,3-diazacyclohexane subrings (1–4) in high yields. The products were characterized by FT-IR, 1H, 13C NMR spectroscopy, elemental analyses, and single crystal X-ray studies. The solid state structures revealed strong intramolecular hydrogen bonding between the pendant phenolic group and the tertiary nitrogen of the corresponding macroring.

2016 ◽  
Vol 69 (3) ◽  
pp. 273
Author(s):  
Bahram Ghanbari ◽  
Barzin Safarkoopayeh (Agheli) ◽  
Reze Kia ◽  
Paul R. Raithby

The reaction of 15–18 membered benzodiazacrown ethers with salicylaldehyde afforded n-membered O2N2-donor macrocyclic ligands mounted with 1,3-diazacyclohexane subrings (1–4) in high yields. The products were characterized by FT-IR, 1H, 13C NMR spectroscopy, elemental analyses, and single crystal X-ray studies. The solid state structures revealed strong intramolecular hydrogen bonding between the pendant phenolic group and the tertiary nitrogen of the corresponding macroring.


2009 ◽  
Vol 64 (11-12) ◽  
pp. 1513-1524 ◽  
Author(s):  
Uwe Monkowius ◽  
Manfred Zabel ◽  
Michel Fleck ◽  
Hartmut Yersin

The P∩N-ligands Ph2Pqn, 1, Ph2 Piqn, 2, Ph2 Ppym, 3, and the As∩N-ligands Ph2Asqn, 4, Ph2Asiqn, 5, (Ph = phenyl, qn = 8-quinoline, iqn = 1-isoquinoline, pym = 2-pyrimidine) have been synthesized, the ligands 2 and 5 for the first time. Their ligand properties were probed by the synthesis of gold(I) complexes. Reaction with (tht)AuCl (tht = tetrahydrothiophene) yielded the chlorogold complexes Ph2RP-Au-Cl (R = qn, 6; iqn, 7; pym, 8) and Ph2RAs-Au-Cl (R = qn, 9; iqn, 10) in high yields. Further treatment of 7 and 8 with one equivalent of AgBF4 provided the complexes [(Ph2Piqn)Au]BF4, 11, [(Ph2Ppym)Au]BF4, 12, and [(Ph2Piqn)Au(tht)]BF4, 14. For comparison, the previously reported complex [(Ph2Ppy)Au]BF4 (py = pyridine), 13, was re-investigated. The compounds were characterized by elemental analyses, mass spectrometry and NMR spectroscopy. In addition, the solid-state structures of 2, 3, 6, 7, 9 - 14 have been determined by X-ray crystallography. The chloro-gold compounds crystallize in the common rod-like structure known from R3EAuCl (R = aryl, E = P, As) complexes without further aggregation via aurophilic interactions. In all cases the phosphine acts as a monodentate ligand. In the solid state compounds 11 - 13 feature an unprecedented cyclic trinuclear aggregation pattern, in which the Au(I) atoms are linearly coordinated by the bridging phosphine ligands forming a cyclic (P-Au-N)3 arrangement. The resulting twelvemembered ring is further stabilized by Au · · · Au interactions. Due to the presence of these Au · · · Au contacts, 11 - 13 are emissive in the solid state but not in solution


1967 ◽  
Vol 45 (14) ◽  
pp. 1699-1706 ◽  
Author(s):  
G. E. Dunn ◽  
Thomas L. Penner

The relative acidities of fifteen 4- and 5-substituted salicylic acids were determined in benzene solution by potentiometric titration. The potentials at half neutralization (h.n.p.) relative to that of salicylic acid were considered to measure the acidities of the substituted acids relative to the parent acid. These potentials, designated by Δhnp, gave a significantly better correlation with Hammett's sigma constants in an equation of the form proposed by Jaffe, Δhnp = ρ1σ1 + ρ2σ2, than in a simple Hammett equation, Δhnp = ρ1σ1. In these equations the subscripts 1 and 2 refer to the position of a substituent relative to the carboxyl group and to the phenolic group respectively. The value of ρ2/ρ1 was found to be 0.4, indicating that the electronic effect of a substituent on the acid strength via the phenolic hydrogen-bonded path is almost half as large as the direct effect through the carboxyl group. These results, together with the fact that in aqueous solution there is very little if any transmission via the phenolic group, are discussed in terms of intramolecular hydrogen bonding of salicylic acids in benzene and in water.


2016 ◽  
Vol 69 (5) ◽  
pp. 489 ◽  
Author(s):  
Sreedhar V. Kumar ◽  
Warrick K. C. Lo ◽  
Heather J. L. Brooks ◽  
Lyall R. Hanton ◽  
James D. Crowley

A family of mono- and di-fac-rhenium tricarbonyl 2-pyridyl-1,2,3-triazole complexes with different aliphatic and aromatic substituents was synthesized in good-to-excellent yields (46–99 %). The complexes were characterized by 1H and 13C NMR spectroscopy, infrared spectroscopy, electronic (UV-visible) spectroscopy, high-resolution electrospray mass spectrometry, and elemental analyses. In four examples, the solid-state structures of the rhenium(i) complexes were confirmed by X-ray crystallography. The family of the mono- and di-rhenium(i) complexes and the corresponding 2-pyridyl-1,2,3-triazole was tested for antimicrobial activity in vitro against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) microorganisms. Agar-based disk diffusion assays indicated that most of the rhenium(i) complexes were active against Staphylococcus aureus and that the cationic rhenium(i) complexes were more active than the related neutral systems. However, in all cases, the minimum inhibitory concentrations for all the complexes were modest (i.e. 16–1024 µg mL–1).


Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 267 ◽  
Author(s):  
Reza Kia ◽  
Azadeh Kalaghchi

The synthesis, characterization, structural and computational studies of Re(I) tricarbonyl bromo complexes bearing alkyl-substituted 1,4-diazabutadiene ligands, [Re(CO)3(1,4-DAB)Br], where 1,4-DAB = N,N-bis(2,4-dimethylbenzene)-1,4-diazabutadiene, 2,4-Me2DAB (1); N,N-bis(2,4-dimethylbenzene)-2,3-dimethyl-1,4-diazabutadiene, 2,4-Me2DABMe (2); N,N-bis(2,4,6-trimethylbenzene)-1,4-diazabutadiene, 2,4,6-Me3DAB (3); and N,N-bis(2,6-diisopropylbenzene)-1,4-diazabutadiene, 2,6-ipr2DAB (4) are reported. The complexes were characterized by different spectroscopic methods such as FT-IR, 1H-NMR, 13C-NMR, and elemental analyses and their solid-state structures were confirmed by X-ray diffraction. In each complex, the Re(I) centre shows a distorted octahedral shape with a facial geometry of carbonyl groups. The gas phase geometry of the complexes was identified by density functional theory. Interesting intermolecular n…π* interactions of complexes 1 and 3 were investigated by non-covalent interaction index (NCI), and natural bond orbital (NBO) analyses. The intramolecular n…σ*, σ…π*, π…σ* interactions were also studied in complexes 3 and 4.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Md. Hasan Zahir

Reaction of Ce3+with p-tert-butylcalix[n]arene (n=4,6,8) yields purple crystalline complexes structurally as [Ce(p-tert-butylcalix[4]arene-3H)2(NO3)(DMF)x](2 −x)DMF (1), [Ce(p-tert-butylcalix[6]arene-4H)2(NO3)(DMF)x](3 −x)DMF (2), and [Ce(p-tert-butylcalix[8]arene-7H)2(NO3)(DMF)6] (3), whereDMF=N,N-dimethylformamide. The properties and coordination characteristics of the three calixarene complexes were determined by elemental analyses, electronic absorption, X-ray absorption spectroscopy (EXAFS), TG-DTA, FT-IR, SEM, and1H-NMR spectroscopy. The effect of various organic solvents on complexes1,2, and3has been discussed based on results from electronic absorption spectra. The polar protic solvents showed the most significant molar extinction coefficients in comparison with those of nonpolar and polar aprotic solvents. The Ce3+ions in the complexes are proved to combine with the ligand phenolic groups, oxygen atoms of DMF molecules, and/or OH−ions.


1992 ◽  
Vol 286 ◽  
Author(s):  
Zhiping Jiang ◽  
Wendell E. Rhine

ABSTRACTThe controlled hydrolysis of Al(O-sec-Bu)3 and Y(O-iso-Pr)3 or the reaction of Y(OOCCH)3 with partially hydrolyzed Al(O-sec-Bu)3 [AlO0.75(O-sec-Bu)1.5] resulted in the formation of soluble polymeric materials. Pyrolysis of these materials under a flow of oxygen led to the formation of yttrium aluminum garnet (YAG) at 650-1500°C. YAG was the only crystalline phase observed during pyrolysis, and the Al/Y ratio of the pyrolysis products and the starting material was identical. However, infrared spectroscopy indicated that carbonate groups and entrained CO2 existed in the products at temperatures up to 1250°C. The pyrolysis chemistry of the precursors and the microstructure of the products were studied by FT-IR, TGA, XRD, SEM and elemental analyses.


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