54220-52-9Relevant academic research and scientific papers
Synthesis, Characterization, and Cytotoxicity of Morpholine-Containing Ruthenium(II) p-Cymene Complexes
Chatterjee, Rishav,Bhattacharya, Indira,Roy, Souryadip,Purkait, Kallol,Koley, Tuhin Subhra,Gupta, Arnab,Mukherjee, Arindam
, p. 12172 - 12185 (2021)
Morpholine motif is an important pharmacophore and, depending on the molecular design, may localize in cellular acidic vesicles. To understand the importance of the presence of pendant morpholine in a metal complex, six bidentate N,O-donor ligands with or without a pendant morpholine unit and their corresponding ruthenium(II) p-cymene complexes (1-6) are synthesized, purified, and structurally characterized by various analytical methods including X-ray diffraction. Complexes 2-4 crystallized in the P21/c space group, whereas 5 and 6 crystallized in the P1ˉ space group. The solution stability studies using 1H NMR support instantaneous hydrolysis of the native complexes to form monoaquated species in a solution of 3:7 (v/v) dimethyl sulfoxide-d6 and 20 mM phosphate buffer (pH? 7.4, containing 4 mM NaCl). The monoaquated complexes are stable for at least up to 24 h. The complexes display excellent in vitro antiproliferative activity (IC50 ca. 1-14 μM) in various cancer cell lines, viz., MDA-MB-231, MiaPaCa2, and Hep-G2. The presence of the pendant morpholine does not improve the dose efficacy, but rather, with 2-[[(2,6-dimethylphenyl)imino]methyl]phenol (HL1) and its pendant morpholine analogue (HL3) giving complexes 1 and 3, respectively, the antiproliferative activity was poorer with 3. MDA-MB-231 cells treated with the complexes show that the acidic vesicles remain acidic, but the population of acidic vesicles increases or decreases with time of exposure, as observed from the dispersed red puncta, depending on the complex used. The presence of the 2,6-disubstituted aniline and the naphthyl group seems to improve the antiproliferative dose. The complex treated MDA-MB-231 cells show that cathepsin D, which is otherwise present in the cytosolic lysosomes, translocates to the nucleus as a result of exposure to the complexes. Irrespective of the presence of a morpholine motif, the complexes do not activate caspase-3 to induce apoptosis and seem to favor the necrotic pathway of cell killing.
Structural studies and applications of water soluble (phenoxy)imine palladium(II) complexes as catalysts in biphasic methoxycarbonylation of 1-hexene
Akiri, Saphan O.,Ojwach, Stephen O.
supporting information, (2021/04/27)
Reactions of the ligands; sodium 4?hydroxy-3-((phenylimino)methyl)benzenesulfonate (L1), sodium 3-(((2,6-dimethylphenyl)imino)methyl)-4-hydroxybenzenesulfonate (L2) and sodium 3-(2,6-diisopropylphenyl)imino)methyl)-4-hydroxybenzenesulfonate (L3) with Pd(OAc)2 afforded the respective palladium(II) complexes [Pd(L1)2] (PdL1), [Pd(L2)2] (PdL2) and [Pd(L3)2] (PdL3). In addition, treatment of the non-water soluble ligands 2-((phenylimino)methyl)phenol (L4), 2-(((2,6-dimethylphenyl)imino)methyl)phenol (L5) and 2-((2,6-diisopropylphenyl)imino)methyl)phenol (L6) with Pd(OAc)2 gave the corresponding complexes [Pd(L4)2] (PdL4), [Pd(L5)2] (PdL5) and [Pd(L6)2] (PdL6) in good yields. Solid state structures of complexes PdL1 and PdL4 established the formation of bis(chelated) square planar neutral compounds. All the complexes formed active catalysts in the methoxycarbonylation of 1-hexene, affording yields of up to 92% within 20 h and regioselectivity of 73% in favour of linear esters. The catalytic activity and selectivity of the complexes depended on the steric encumbrance around the coordination centre. The water soluble complexes displayed comparable catalytic behaviour to the non-water soluble systems. The complexes could be recycled five times with minimal changes in both the catalytic activities and regio-selectivity.
Dinuclear iminophenoxide copper complexes in rac-lactide polymerisation
Daneshmand, Pargol,Pinon, Leena,Schaper, Frank
, p. 10147 - 10161 (2018/08/09)
Dinuclear bis(R′-(R′′-iminomethyl)phenoxide) copper complexes L2Cu2(μ-OR)2 were prepared from the reaction of copper methoxide with ROH and LH (ROH = dimethylaminoethanol or pyridylmethanol, R′ = H, 4,6-tBu, 1,3-Cl, R′′ = benzyl, cyclohexyl, diphenylmethyl and 2,6-dimethylphenyl). Preparation was complicated by formation of homoleptic L2Cu and only 9 of the 24 possible combinations could be prepared. All complexes were characterized by single crystal X-ray diffraction studies and crystallized as dinuclear penta-coordinated complexes. Homoleptic complexes L2Cu were inactive in lactide polymerization at room temperature. Most heteroleptic complexes showed modest to good activities with full conversion in less than 6 h at room temperature. Complexes with R′ = H showed poor molecular weight control, complexes with R′ = Cl were inactive in polymerization. In pyridylmethoxide-containing complexes, only one alkoxide initiated chain growth. All complexes produced atactic polymer.
Olefin isomerization reactions catalyzed by ruthenium hydrides bearing Schiff base ligands
Ding, Fu,Doorslaer, Sabine Van,Cool, Peggie,Verpoort, Francis
experimental part, p. 601 - 607 (2011/10/18)
A series of in situ-generated ruthenium hydride complexes Ru(PPh 3)2(CO)H(Ln) (n = a-h) incorporating a Schiff base ligand was investigated for the isomerization of olefins. 1H-NMR was used to characterize the new hydride species in combination with 31P-NMR. Allylbenzene and 1-octene were used as model substrates. Temperature, solvents and catalyst/substrate mole ratio were taken into account as parameters to optimize the isomerization reaction. All catalysts showed the best performance in 2-butanol, suggesting that the catalytic activity depends not only strongly on the steric and electronic environment of the ruthenium but also on the chosen solvent.
Assignment and conformational investigation of asymmetric phenylindenylidene ruthenium complexes bearing N, O-bidentate ligands
Hendrickx,Drozdzak,Verpoort,Martins
experimental part, p. 443 - 449 (2011/08/04)
The NMR conformational study of three asymmetric phenylindenylidene ruthenium complexes 4.1-4.3, is presented. Complete 1H and 13C assignments could be obtained for 4.1-4.3 in benzene solution from multiple 2D homonuclear and heteron
Bis(salicylaldiminato)titanium complexes containing bulky imine substituents: Synthesis, characterization and ethene polymerization studies
Paerssinen, Antti,Luhtanen, Tommi,Klinga, Martti,Pakkanen, Tapani,Leskelae, Markku,Repo, Timo
, p. 2100 - 2109 (2007/10/03)
A series of titanium complexes bearing two anionic [N, O-] bidentate salicylaldiminato ligands, namely bis[(N-salicylidene)anilinato]titanium(IV) dichloride (1), bis[(N-salicylidene)-2,6-dimethylamlinato]titanium(IV) dichloride (2), bis[(N-salicylidene)-2,6-di-i- propylanilinato]titanium(IV) dichloride (3), bis [(N-salicylidene) - (1-naphthalenylimino)]titanium(IV) dichloride (4), bis[(N-salicylidene)-2,6-difruoroanilinato]titanium(IV) dichloride (5), and bis[(N-3-fluorosalicylidene)-2,6-difluoroanilinato]titanium(IV) dichloride (6) have been synthesized with good yields by a two-step procedure. The X-ray structure analysis reveals that in complex 2, titanium has a distorted octahedral coordination sphere in which the oxygen atoms and the chloride ligands form the basal plane. Both the chloride and the phenoxy moieties have a cis orientation and the angle between the chloride ligands is 93.05°. The imine nitrogen atoms complete the octahedral coordination of the Ti center by occupying the axial positions. The newly synthesized (2 and 4-6) and already known complexes (1 and 3) were introduced in detailed ethene-polymerization studies. The activities achieved were low to moderate depending on the size and nature of the imino substituents. The polyethenes (PEs) produced had high molar masses, and the modalities of the molecular weight distributions varyied with polymerization temperature. Based on the results of ab initio calculations and on the experimental data obtained, an explanation for uni- and bimodal polymerization behavior and the differences in catalytic activities are given. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Synthesis and spectral [IR, 1H, 13C, and 11B] properties of 2-(N-arylsalicylaldimino)- 4,4,5,5-tetramethyl-1,3,2-dioxaborolanes
Goyal,Singh
, p. 638 - 641 (2007/10/03)
Reactions in 1:1 molar ratio of 2-isopropoxy-4, 4, 5, 5tetramethyl-1, 3, 2-dioxaborolane with N-arylsali-cylaldimines (LH=HOC6 H4CH=NC6H5, HOC6H4CH=NC6H4Me2-2,6, HOC6H4CH=NC6H2Me3-2,4,6, HOC6H4CH=NC6H3Et2-2, 6, and HOC6H4CH=NC6H3Pr2-2, 6 in benzene afford new cyclic compounds of boron containing pinacolate and salicylaldiminate groups. These new derivatives have been characterized by elemental analysis and spectroscopic [IR, NMR (1H, 13C, and 11B)] studies as well as by molecular weight determinations.
Development of a diversity-based approach for the discovery of stereoselective polymerization catalysts: Identification of a catalyst for the synthesis of syndiotactic polypropylene
Tian, Jun,Coates, Geoffrey W.
, p. 3626 - 3629 (2007/10/03)
Combinatorial methods have recently been used to aid in the discovery of new pharmaceuticals and catalysts for organic synthesis. A simple and inexpensive strategy for using combinatorial methods to discover polymerization catalysts is reported, and using it enabled a new catalyst (1, see scheme) for the synthesis of syndiotactic polypropylene to be identified.
Transition metals complexed to ordered mesophases. VIII. Cyclopalladated p-azoxyanisole complexes. Crystal structure of -2)-4-methoxyphenyl-2-ato>palladium(II)
Ghedini, Mauro,Morrone, Stefania,Munno, Giovanni De,Crispini, Alessandra
, p. 281 - 291 (2007/10/02)
The synthesis and characterization of the cyclopalladated p-azoxyanisole chloro-bridged dimer 2, 1, is reported and its reactions with some salicylideneaniline derivatives (HL1-5) are described. 1H NMR spectral observations indicate that except for the mononuclear products are ca 5:1 mixtures of N-trans and N-cis isomers.In the HL4 case (HL4 = salicylidene(2,4-dimethyl)aniline) the only product which was detected is the N-trans isomer.The crystal structure of trans- (HL1 = salicylideneaniline) (3-trans) is monoclinic.
