Monocarbon monoxide complexes of iron(II): synthesis and X-ray structural characterization

Goedken, Virgil L.; Molin-Case, JoAnn; Whang, Young-ae

doi:10.1039/c39730000337

Cited by 58 publications

(53 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The bonding situation is different for the other Gd which is connected to each of the N-atoms of the two tmtaa-ligands on the same side of the ligand where the C 6 H 4 -fragments are tipped to that is realized by a 90° rotation of the third tmtaaligand around the Gd-Gd axis. A similar structure is expected for 2 based upon the 1 4 ] or p-benzoquinone (1 equivalent per cerium) with 1 or 2 in tetrahydrofuran or toluene, respectively. Complex 3 may be crystallized by slow vapor diffusion of pentane into a concentrated toluene solution as deep green, air-stable shiny cubes which incorporate half a molecule of pentane per cerium.…”

mentioning

confidence: 75%

“…However, the molecule does not melt to 310 °C nor sublime in an ampoule under static vacuum up to temperatures of 350 °C; instead it decomposes and the decomposition products are identified as tmtaaH 2 , an unidentified green oil and an insoluble red-brown residue. Ce 2 (tmtaa) 3 is not formed under these conditions as determined by 1 H NMR spectroscopy. The 1 H and 13 C NMR spectra of 3 show only one set of CH and CH 3 units consistent with a molecule of high symmetry.…”

mentioning

confidence: 99%

“…[1][2][3][4][5] The [14]annulene nomenclature is informative since it connects tmtaaH 2 to two related classes of ligands that have an extensive chemistry, viz., [8]-annulene, otherwise known as cyclooctatetraene, cot, and [16]-annulenes, the porphyrins, porphH 2 , and phthalacyanines, pcH 2 . Although all of these ligands form stable dianions, their electronic structure and therefore the electronic properties of their complexes are different.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Synthesis and magnetic properties of cerium macrocyclic complexes with tetramethyldibenzotetraaza[14]annulene, tmtaaH2

2006

View full text Add to dashboard Cite

3 and tmtaaH 2 , the macrocyclic ligand 6,8,15,17-tetramethyldibenzotetraaza[14]annulene, depending on the stoichiometry, solvent and temperature. The crystal structure of Ce(tmtaa) 2 is isostructural with Zr(tmtaa) 2 , however magnetic susceptibility measurements in the range 5-300 K show that Ce(tmtaa) 2 is not diamagnetic, but is a temperature-independent paramagnet (TIP), similar to Ce(cot) 2 , cerocene. 2 , and phthalacyanines, pcH 2 . Although all of these ligands form stable dianions, their electronic structure and therefore the electronic properties of their complexes are different. The tmtaa 2-is a 24 π-electron system (4nπ, n= 6) that is not Hückel aromatic. The negative charge is not delocalized over its entire framework, but is localized on the four nitrogen atoms, that carry a total negative charge of -0.98 e, and the two β-carbon atoms in the imidinate ring that carry a -0.24 e charge, NC α (Me)C β (H)C α (Me)N. 6,7 The tmaa 2-is therefore not planar but is saddle shaped with idealized C 2v symmetry. 8 The cot 2-(4nπ+2, n=2) and porph 2-(4nπ+2, n=6) are aromatic and the negative charge is delocalized over the planar rings. Pr, Nd, Sm, Gd, Tb, Er and Yb. 30 In this paper the synthesis and physical properties of Ce(tmtaa) 2 and related complexes are described. Results and Discussion Synthesis and StructureThe synthesis of the complexes involves the reaction of tmtaaH 2 with Ce[N(SiMe 3 ) 2 ] 3 in various molar ratios. Proton transfer reactions of Ce[N(SiMe 3 ) 2 ] 3 , the pK a of (Me 3 Si)NH in thf is 26, 31 depend critically on the solvent, concentration of the reactants, and temperature. These details are given in the Experimental Section, which are reproducable when close attention to detail is observed, and shown schematically in Scheme 1. Solutions of complexes Ce(tmtaa)(tmtaaH) (1) and Ce 2 tmtaa 3 (2) are extremely sensitive to trace amounts of air, which result in formation of Ce(tmtaa) 2 (3), which is stable to air and moisture. Deliberate oxidation of either 1 or 2 is therefore an excellent synthetic route to 3.Ce(tmtaa)(tmtaaH) (1) not when Ln = Ce. Crystals of Ce(tmtaa)(tmtaaH) grown from toluene, were twinned, the tmtaa and tmtaaH fragments are disordered, and therefore the X-ray diffraction pattern could not be resolved. However, the 2:1 stoichiometry of the complex is confirmed. Ce(tmtaa)(tmtaaH) (1) decomposes slowly to Ce(tmtaa) 2 (3) and tmtaaH 2 (ratio 1:1) in C 6 D 6 at 65 °C over 14 days. Close inspection of the decomposition process reveales that after one day small amounts of Ce 2 (tmtaa) 3 (2) and tmtaaH 2 are detected in the 1 H NMR spectrum. Over the time priod of two weeks the resonances due to 2 increase then decrease as 3 is formed and the resonances due to tmtaaH 2 continue to increase until a steady state is reached. The decomposition does not eliminate hydrogen since the latter is not observed in the 1 H NMR spectrum and the addition of dehydroanthracene does not yield anthracene. It seems reasonable to suggest that the initial decomposition step of 1 is the format...

show abstract

mentioning

confidence: 75%

mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and magnetic properties of cerium macrocyclic complexes with tetramethyldibenzotetraaza[14]annulene, tmtaaH2

2006

View full text Add to dashboard Cite

show abstract

“…The Schiff bases were prepared according to the method described in the literature [26] (Scheme 1), yielding 60%. The IR, 1 H NMR, 13 C NMR, and the UV-vis absorption spectra were in good agreement with the published data.…”

Section: Synthesismentioning

confidence: 99%

Kinetic studies of the interaction between organotin(IV)chlorides and tetraaza Schiff bases: Synthesis and characterization of some novel tin(IV) Schiff base complexes

Asadi

2011

Int J of Chemical Kinetics

View full text Add to dashboard Cite

In this article the kinetics of the interaction between the teteraaza Schiff bases as donor with organotin(IV)chlorides as acceptor was studied in acetonitrile. Teteraaza Schiff bases are (Me4‐Bzo2[14]tetraeneN4) (tmtaa), (Me4‐4‐CH3Bzo2[14]tetraeneN4) (Metmtaa), (Me4‐4‐ClBzo2[14]tetraeneN4) (Cltmtaa), i.e., [(Me4‐Bzo2[14]tetraeneN4)] means that (5,7,12,14‐tetramethyldibenzo[b,i][1,4,8,11] tetraazacyclotetradecine) (tmtaa) and organotin(IV)chlorides are methyltin(IV) trichloride, phenyltin(IV)trichloride, dimethyltin (IV)dichloride, diphenyltin(IV) dichloride, and dibutyltin(IV)dichloride. The kinetic parameters and the second‐order k2 rate constants show the donor properties of tetraaza Schiff bases as Me4‐4‐CH3Bzo2[14]tetraeneN4 > Me4‐Bzo2[14]tetraeneN4 > Me4‐4‐ClBzo2[14]tetraeneN4 and also the acceptor properties of organotin(IV)chlorides as PhSnCl3 > MeSnCl3 > Ph2SnCl2 > Me2SnCl2 > Bu2SnCl2. An excellent linearity of kobs vs. the molar concentration of the acceptor, the high span of k2 values, the large negative values of ΔS≠, and the low ΔH≠ values suggest an associative (A) mechanism for the acceptor–donor interaction. © 2011 Wiley Peiodicals, Inc. Int J Chem Kinet 43: 247–254, 2011

show abstract

“…These invaluable studies clearly delineated the fundamental characteristics of macrocyclic ligand complexes through the evaluation of their general stabilities, ligand field properties and reactivates. Recently, several numbers of highly unsaturated to conjugated macrocyclic ligand complexes have been prepared and investigated [1][2][3]. The fact that macrocyclic ligand complexes are involved in a number of fundamental biological systems has long been recognized.…”

Section: Introductionmentioning

confidence: 99%

Synthesis, structural and catalytic activity of binaphthyl macrocyclic complexes

Hanafy

Maki

Mostafa

2007

Transition Met Chem

View full text Add to dashboard Cite

The binaphthyl macrocyclic ligand, N,N¢-diethyl-[3,3¢-(2,2¢-dihydroxy-1,1¢-binaphthyl)carboxamide]-2,2¢-dihydroxy-1,1¢-binaphthyl-3,3¢-dicarboxylic acid (DDCDB), has been synthesized and investigated. The ligand (DDCDB) and its metal complexes involving Cu II , Zn II , UO 2 II , Th IV , Ce III , Mo VI and W VI ions have been prepared and characterized by spectral (i.r., u.v.-vis.), elemental analyses, magnetic moments and thermal analyses measurements. DDCDB behaves as a tridentate ligand towards Cu II , Zn II and UO 2 II ions coordinating via CO, NH and the deprotonated naphthyl OH groups in a ratio of 2:1 (M:L). On the other hand, DDCDB behaves in a bidentate manner coordinatingvia the NH and the deprotonated naphthyl OH groups only in case of the Th IV , Ce III , Mo VI , and W IV ions and in ratio 1:1 (M:L). Results of thermal measurements confirm the existence of solvent molecules inside and outside the coordination sphere. Th VI complex has been applied for the hydrolysis of phosphodiester and the results show a significant rate enhancement of $5.8 million fold with respect to the auto-hydrolysis of bis-(p-nitrophenyl) phosphate (BNPP) under the same conditions Also, Cu II complex accelerates the photodegradation of the hazardous pollutant (acid green dye) in the presence of hydrogen peroxide by degrading 90% of the dye within 23 min.

show abstract

Monocarbon monoxide complexes of iron(II): synthesis and X-ray structural characterization

Cited by 58 publications

References 1 publication

Synthesis and magnetic properties of cerium macrocyclic complexes with tetramethyldibenzotetraaza[14]annulene, tmtaaH2

Synthesis and magnetic properties of cerium macrocyclic complexes with tetramethyldibenzotetraaza[14]annulene, tmtaaH2

Kinetic studies of the interaction between organotin(IV)chlorides and tetraaza Schiff bases: Synthesis and characterization of some novel tin(IV) Schiff base complexes

Synthesis, structural and catalytic activity of binaphthyl macrocyclic complexes

Contact Info

Product

Resources

About