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1.
Hannah Dengel Dr. Crispin Lichtenberg 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(51):18465-18475
The synthetic access to cationic bismuth compounds based on simple, monodentate, synthetically useful amido ligands, [Bi(NR2)2(L)n]+, has been investigated (R=Me, iPr, Ph; L=neutral ligand). With [BPh4]? as a counteranion, the formation of contact ion pairs and subsequent phenyl transfer from B to Bi is observed. An intermediate of this reaction, [Bi(NMe2)2(HNMe2)(BPh4)] ( 1 ), could be isolated and fully characterized. The use of a fluorinated tetraarylborate as a counteranion leads to more stable cationic bismuth amides. The solvent‐separated ion pairs [Bi2(μ2‐NMe2)2(NMe2)2(thf)6]2+ ( 4 ) and [Bi(NiPr2)2(thf)3]+ ( 5 ) were fully characterized, with [B(3,5‐C6H3(CF3)2)4]? anions balancing the positive charge. The coordination chemistry, aggregation in solution, and spectroscopic features of these compounds were investigated. Compounds 4 and 5 show an increased reactivity towards diisopropylcarbodiimide compared to their neutral parent compounds. These reactions result in formation of the first cationic bismuth guanidinates. Characterization techniques include 1H, 11B, 13C, 15N, 19F, and 31P (VT)NMR and IR spectroscopy, single crystal X‐ray diffraction analysis, and DFT calculations. 相似文献
2.
Dr. Anna Hanft Dr. Dennis Rottschäfer Nele Wieprecht Felix Geist Dr. Krzysztof Radacki Priv.-Doz. Dr. Crispin Lichtenberg 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(57):14250-14262
Aminotroponiminate (ATI) ligands are a versatile class of redox-active and potentially cooperative ligands with a rich coordination chemistry that have consequently found a wide range of applications in synthesis and catalysis. While backbone substitution of these ligands has been investigated in some detail, the impact of electron-withdrawing groups on the coordination chemistry and reactivity of ATIs has been little investigated. We report here Li, Na, and K salts of an ATI ligand with a nitro-substituent in the backbone. It is demonstrated that the NO2 group actively contributes to the coordination chemistry of these complexes, effectively competing with the N,N-binding pocket as a coordination site. This results in an unprecedented E/Z isomerisation of an ATI imino group and culminates in the isolation of the first “naked” (i. e., without directional bonding to a metal atom) ATI anion. Reactions of sodium ATIs with silver(I) and tritylium salts gave the first N,N-coordinated silver ATI complexes and unprecedented backbone substitution reactions. Analytical techniques applied in this work include multinuclear (VT-)NMR spectroscopy, single-crystal X-ray diffraction analysis, and DFT calculations. 相似文献
3.
Five coordination compounds of bismuth, lanthanum and praseodymium nitrate with the oxygen‐coordinating chelate ligand (iPrO)2(O)PCH2P(O)(OiPr)2 (L) are reported: [Bi(NO3)3(L)2] ( 1 ), [La(NO3)3(L)2] ( 2 ), [Pr(NO3)3(L)2] ( 3 ), [La(NO3)3(L)(H2O)] ( 4 ) and [Pr(NO3)3(L)(H2O)] ( 5 ). The compounds were characterized by means of single crystal X‐ray crystallography, 1H and 31P NMR spectroscopy in solution, solid‐state 31P NMR spectroscopy, IR spectroscopy, DTA‐TG measurements ( 1 , 2 and 4 ), conductometry and electrospray ionization mass spectrometry (ESI‐MS). In addition, DFT calculations for model compounds of 1 and 2 support our experimental work. In the solid state mononuclear coordination compounds were observed for 1 — 3 , whereas compounds 4 and 5 gave one‐dimensional hydrogen‐bonded polymers via water‐nitrate coordination. Despite of the similar ionic radii of bismuth(III), lanthanum(III) and praseodymium(III) for a given coordination number the bismuth and lanthanide compounds 1 — 3 are not isostructural. The bismuth compound 1 shows a 9‐coordinate bismuth atom whereas lanthanum(III) and praseodymium(III) atoms are 10‐coordinate in the lanthanide complexes 2 — 5 . The general LnO10 coordination motif in compounds 2 — 5 is best described as a distorted bi‐capped square antiprism. The BiO9 polyhedron might be deduced from the LnO10 polyhedron by replacing one oxygen ligand with a stereochemically active lone pair. The one‐to‐one complexes 4 and 5 dissociate in solution to give the corresponding one‐to‐two complexes 2 and 3 , respectively, and solvated Ln(NO3)3. In contrast to the lanthanides, the one‐to‐two bismuth complex 1 is less stable in CH3CN solution and partially dissociates to give solvated Bi(NO3)3 and (iPrO)2(O)PCH2P(O)(OiPr)2. 相似文献
4.
Marcus B. Kindervater Katherine M. Marczenko Ulrike Werner‐Zwanziger Saurabh S. Chitnis 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(23):7932-7937
Reaction of a tethered triamine ligand with Bi(NMe2)3 gives a Bi triamide, for which a BiI electronic structure is shown to be most appropriate. The T‐shaped geometry at bismuth provides the first structural model for edge inversion in bismuthines and the only example of a planar geometry for pnictogen triamides. Analogous phosphorus compounds exhibit a distorted pyramidal geometry because of different Bi?N and P?N bond polarities. Although considerable BiI character is indicated for the title Bi triamide, it exhibits reactivity similar to BiIII electrophiles, and expresses either a vacant or a filled p orbital at Bi, as evidenced by coordination of either pyridine N‐oxide or W(CO)5. The product of the former shows evidence of coordination‐induced oxidation state change at bismuth. 相似文献
5.
N. N. Golovnev A. I. Petrov A. O. Lykhin A. A. Leshok 《Russian Journal of Inorganic Chemistry》2012,57(4):596-600
The formation constants of bismuth(III) methylthiourea complexes in aqueous solution were determined at 298 K and an acidity
of 2 M HClO4 using the “ligand-oxidized ligand species” potentiometric method and the methylthiourea (mtu)-symmetric dimethylformamidine
disulfide (mFDS) redox pair. The formation function was obtained, and the conditional (β
n
*) and true (β
n
) formation constants of Bi(mtu)
n
3+ (1 ≤ n ≤ 8) were calculated. The value of β1 and the formation of complexes with coordination numbers higher than six was confirmed by spectrophotometry. 相似文献
6.
Synergistic Catalytic Effect of a Series of Energetic Coordination Compounds based on Tetrazole‐1‐acetic Acid on Thermal Decomposition of HMX
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A series of energetic coordination compounds [Co(tza)2}n ( 1 ), [Bi(tza)3]n ( 2 ), {[Cu4(tza)6(OH)2] · 4H2O}n ( 3 ), [Mn(tza)2]n ( 4 ), {[Bi(tza)(C2O4)(H2O)] · H2O}n ( 5 ) and [Fe3O(tza)6(H2O)3]NO3 ( 6 ) based on tetrazole‐1‐acetic acid (Htza) were synthesized though environmentally friendly methods. The coordination compounds were characterized by elemental analyses, IR spectroscopy, single‐crystal and powder X‐ray diffraction (PXRD), thermogravimetric analyses (TG), and differential scanning calorimetry (DSC). Their catalytic performances and the synergetic catalytic effects between 1 and 2 , 3 and 4 , 5 and 6 on the thermal decomposition of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) were all investigated by DSC. The results revealed that compounds 1 – 6 are thermally stable energetic compounds and they all exhibit high catalytic action for HMX thermal decomposition. The catalytic effects of the compounds on HMX thermal decomposition are closely related to the oxides, which come from the decomposition of the compounds, but have no positive relationships with the heat releases of the compounds themselves. Moreover, the synergetic catalytic effects between 1 and 2 , 3 and 4 , 5 and 6 were observed. Their mixtures at different mass ratio have different synergetic catalytic effects, and the sequence of the biggest synergetic index (SI) in each system is copper‐manganese system (compounds 3 and 4 ) > iron‐bismuth system (compounds 5 and 6 ) > cobalt‐bismuth system (compounds 1 and 2 ), indicating that the synergistic catalytic effects are mainly related to the combination and the proportion of the compounds. 相似文献
7.
Lars Wesemann 《无机化学与普通化学杂志》2004,630(10):1349-1356
Most of the divalent compounds of tin have a lone pair and hence can act as donors. In tin‐transition metal chemistry neutral molecules as well as anions have been studied as ligands. This research report summarizes recent research on coordination compounds with a closo‐heteroborate cage compound stanna‐closo‐dodecaborate [SnB11H11]2?. The syntheses of the first coordination compounds and studies on the ligand abilities of this tin borate are discussed in this article. 相似文献
8.
Jacqueline Ramler Priv.-Doz. Dr. Crispin Lichtenberg 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(45):10250-10258
Three-coordinate cationic bismuth compounds [Bi(diaryl)(EPMe3)][SbF6] have been isolated and fully characterized (diaryl=[(C6H4)2C2H2]2−, E=S, Se). They represent rare examples of molecular complexes with Bi⋅⋅⋅EPR3 interactions (R=monoanionic substituent). The 31P NMR chemical shift of EPMe3 has been found to be sensitive to the formation of LA⋅⋅⋅EPMe3 Lewis acid/base interactions (LA=Lewis acid). This corresponds to a modification of the Gutmann–Beckett method and reveals information about the hardness/softness of the Lewis acid under investigation. A series of organobismuth compounds, bismuth halides, and cationic bismuth species have been investigated with this approach and compared to traditional group 13 and cationic group 14 Lewis acids. Especially cationic bismuth species have been shown to be potent soft Lewis acids that may prefer Lewis pair formation with a soft (S/Se-based) rather than a hard (O/N-based) donor. Analytical techniques applied in this work include (heteronuclear) NMR spectroscopy, single-crystal X-ray diffraction analysis, and DFT calculations. 相似文献
9.
The bismuth tris(triorganosilanolates) [Bi(OSiR3)3] ( 1 , R = Me; 2 , R = Et; 3 , R = iPr) were prepared by reaction of R3SiOH with [Bi(OtBu)3]. Compound 1 crystallizes in the triclinic space group with Z = 2 and the lattice constants a = 10.323(1) Å, b = 13.805(1) Å, c = 21.096(1) Å and α = 91.871(4)°, β = 94.639(3)°, γ = 110.802(3)°. In the solid state compound 1 is a trimer as result of weak intermolecular bismuth‐oxygen interactions with Bi–O distances in the range 2.686(6)–3.227(3) Å. The coordination at the bismuth atoms Bi(1) and Bi(3) is best described as 3 + 2 coordination whereas Bi(2) shows a 3 + 3 coordination. The intramolecular Bi–O distances fall in the range 2.041(3)–2.119(3) Å. Compound 3 crystallizes in the orthorhombic space group Pbcm with Z = 4 and the lattice constants a = 7.201(1) Å, b = 23.367(5) Å and c = 20.893(1) Å, whereas the triethylsilyl‐derivative 2 is liquid. In contrast to [Bi(OSiMe3)3] ( 1 ) compound 3 is monomeric in the solid state, but shows similar intramolecular Bi–O distances in the range 1.998(2)–2.065(5) Å. The bismuth silanolates are highly soluble in common organic solvents and strongly moisture sensitive. Compound 1 shows the lowest thermal stability. 相似文献
10.
Björn Hildebrandt Dr. Stephan Raub Prof. Dr. Walter Frank Prof. Dr. Christian Ganter 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(21):6670-6678
A new synthetic route to complexes of the cationic N‐heterocyclic carbene ligand 2 has been developed by the attachment of a cationic pentamethylcyclopentadienylruthenium ([RuCp*]+) fragment to a metal‐coordinated benzimidazol‐2‐ylidene ligand. The coordination chemistry and the steric and electronic properties of the cationic carbene were investigated in detail by experimental and theoretical methods. X‐ray structures of three carbene–metal complexes were determined. The cationic ligand 2 is a poorer overall electron donor relative to the related neutral carbene, which is evident from cyclic voltammetry (CV) and IR measurements. 相似文献
11.
Reaction of N‐isopropyl‐2‐(isopropylamino)troponimine, {(i‐Pr)2ATI}H, with fac‐[W(CO)3(NCMe)3] yield the complex tungsten‐tetracarbonyl‐N, N'‐diisopropyl‐1, 2‐diimino‐3, 5‐cycloheptadiene ( 1 ), in which the ligand is tautomerized from the enamino to the imino isomer. As a result of the rearrangement the conjugate 10 π electron system of the ligand is destroyed. Further, treatment of compound 1 with an excess of KH in THF leads to the ionic complex [K(THF)2][{(i‐Pr)2ATI}W(CO)4] ( 2 ). In the presence of diglyme the corresponding complex [K(diglyme)2][{(i‐Pr)2ATI}W(CO)4] ( 3 ) is obtained. All compounds have been characterized by spectroscopic methods. Complex 1 has also been investigated by single crystal X‐ray diffraction. 相似文献
12.
《Journal of Coordination Chemistry》2012,65(15):2583-2591
A coordination compound based on tetrazole acetic acid (Htza) and bismuth(III), [Bi(tza)3] n , was synthesized and characterized by single crystal X-ray diffraction analysis, elemental analysis, FT-IR, and 1H NMR spectroscopy. The crystallographic data show that the crystal belongs to monoclinic, P21/n space group, a?=?0.91968(19)?nm, b?=?0.94869(19)?nm, c?=?1.7824(4)?nm, β?=?101.488(3)°, and Z?=?4. The central bismuth(III) is nine-coordinate by three nitrogens from three tetrazole rings and six oxygens of the carboxylate of another three tza? ions, with each tza? tridentate, chelating, bridging coordination. The coordination bonds and the intramolecular hydrogen bonds make the complex pack into a layered structure in polymer form. The thermal decomposition mechanism of the title complex was investigated by DSC and TG-DTG techniques. Under nitrogen at a heating rate of 10°C?min?1, thermal decomposition of the complex contains two intense exothermic processes between 217.4°C and 530.3°C in the DSC curve; the final decomposed residue at 570°C was Bi2O3. Sensitivity tests showed that [Bi(tza)3] n was sensitive to impact and flame stimulus. 相似文献
13.
The role of intramolecular metal???π‐arene interactions has been investigated in the solid‐state structures of a series of main group compounds supported by the bulky amide ligands, [N(tBuAr≠)(SiR3)]? (tBuAr≠=2,6‐(CHPh2)2‐4‐tBuC6H2, R=Me, Ph). The lithium and potassium amide salts showed different patterns of solvation and demonstrated that the SiPh3 substituent is able to be involved in stabilizing the electrophilic metal. These group 1 metal compounds served as ligand transfer reagents to access a series of bismuth(III) halides. Chloride extraction from Bi(N{tBuAr≠}{SiPh3})Cl2 using AlCl3 afforded the 1:1 salt [Bi(N{tBuAr≠}{SiPh3})Cl][AlCl4]. This was accompanied by a significant rearrangement of the stabilizing π‐arene contacts in the solid‐state. Attempted preparation of the corresponding tetraphenylborate salt resulted in phenyl‐transfer and generation of the neutral Bi(N{tBuAr≠}{SiPh3})(Ph)Cl. 相似文献
14.
Mahsa Armaghan Ezzat Najafi Tim-Oliver Knedel Walter Frank Christoph Janiak 《无机化学与普通化学杂志》2020,646(22):1861-1868
Three d10-transition-metal coordination compounds [Cd(tfpb)2(4-bpmh)]n ( 1 ), [Cd(9-aca)(NO3)(OHCH3)(4-bpmh)]n ( 2 ) and [Zn2(dpp)4(4-bpmh)] ( 3 ) with the bridging ligand 4-bpmh were synthesized [4-bpmh = 1,2-bis(pyridin-4-ylmethylene)hydrazine, tfpb = 4,4,4-trifluoro-1-phenylbutane-1,3-dionate, 9-aca = anthracene-9-carboxylate, dpp = 1,3-diphenylpropane-1,3-dionate]. Compounds 1 – 3 were characterized by FT-IR spectroscopy, elemental analysis, and structurally authenticated by X-ray crystallography. Compounds 1 – 3 are constructed by an O,O'-donor ligand including chelating β-diketonates (tfpb, dpp) in 1 and 3 and a carboxylate ligand (9-aca) in 2 in combination with a linear neutral bidentate and bridging N-ligand (4-bpmh). The assembly and action of the bridging 4-bpmh ligand leads to one-dimensional coordination polymers in 1 , 2 and to a dinuclear coordination complex in 3 . The structures and the solid-state supramolecular interactions for studying the crystal packing fashions of 1 – 3 were analyzed. The supramolecular interactions including hydrogen bonding, C–H ··· π, π ··· π, and C–F ··· π in 1 , 2 , and 3 were founded. 相似文献
15.
Dr. Alex J. Plajer Dr. Andrew D. Bond Prof. Dominic S. Wright 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(1):289-297
Phosph(III)azanes, featuring the heterocyclobutane P2N2 ring, have now been established as building blocks in main-group coordination and supramolecular compounds. Previous studies have largely involved their use as neutral P-donor ligands or as anionic N-donor ligands, derived from deprotonation of amido-phosphazanes [RNHP(μ-NR)]2. The use of neutral amido-phosphazanes themselves as chelating, H-bond donors in anion receptors has also been an area of recent interest because of the ease by which the proton acidity and anion binding constants can be modulated, by the incorporation of electron-withdrawing exo- and endo-cyclic groups (R) and by the coordination of transition metals to the ring P atoms. We observed recently that the effect of P,N-chelation of metal atoms to the P atoms of cis-[(2-py)NHP(μ-NtBu)]2 (2-py=2-pyridyl) not only pre-organises the N−H functionality for optimum H-bonding to anions but also results in a large increase in anion binding constants, well above those for traditional organic receptors like squaramides and ureas. Here, we report a broader investigation of ligand chemistry of [(2-py)NHP(μ-tNBu)]2 (and of the new quinolyl derivative [(8-Qu)NHP(μ-NtBu)]2 (8-Qu=8-quinolyl). The additional N-donor functionality of the heterocyclic substituents and its position has a marked effect on the anion and metal coordination chemistry of both species, leading to novel structural behaviour and reactivity compared to unfunctionalized counterparts. 相似文献
16.
Jobha A. Johnson Arun Ashokan Ashish K. Chalana Alex P. Andrews Ajay Venugopal 《无机化学与普通化学杂志》2017,643(9):607-611
The first examples of neutral and cationic bismuth complexes bearing β‐ketoiminato ligands were isolated by employing salt metathesis route. BiCl3 reacts with [O=C(Me)]CH[C(Me)N(K)Ar] ( 1 ) resulting in a homoleptic β‐ketoiminato bismuth complex Bi[{O=C(Me)}CH{C(Me)NAr}]3 ( 2 ). The reaction between BiCl3 and [(CH2)2{N(K)C(Me)CHC(Me)=O}2] ( 3 ) leads to the formation of a cationic bismuth complex [Bi{(CH2)2(NC(Me)CHC(Me)=O)2}]4[Bi2Cl10] ( 4 ). 相似文献
17.
Nitrene Insertion into CC and CH Bonds of Diamide Diimine Ligands Ligated to Chromium and Iron
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Spencer P. Heins Wesley D. Morris Prof. Peter T. Wolczanski Emil B. Lobkovsky Prof. Thomas R. Cundari 《Angewandte Chemie (International ed. in English)》2015,54(48):14407-14411
The impact of redox non‐innocence (RNI) on chemical reactivity is a forefront theme in coordination chemistry. A diamide diimine ligand, [{‐CH?N(1,2‐C6H4)NH(2,6‐iPr2C6H3)}2]n (n=0 to ?4), (dadi)n, chelates Cr and Fe to give [(dadi)M] ([ 1 Cr(thf)] and [ 1 Fe]). Calculations show [ 1 Cr(thf)] (and [ 1 Cr]) to have a d4 Cr configuration antiferromagnetically coupled to (dadi)2?*, and [ 1 Fe] to be S=2. Treatment with RN3 provides products where RN is formally inserted into the C? C bond of the diimine or into a C? H bond of the diimine. Calculations on the process support a mechanism in which a transient imide (imidyl) aziridinates the diimine, which subsequently ring opens. 相似文献
18.
The reaction of 2-hydroxy-N-phenylbenzamide with 2-aminobenzenethiol yielded 2-hydroxy-N-phenylbenzamidebenzothiazoline (H2-Saly · BTZ/HO⋂N⋂SH). The reaction of H2-Saly · BTZ with PhSbCl2, SbCl3, and BiCl3 under varied reaction conditions (microwave, as well as conventional method) gave corresponding antimony( III) and bismuth(III)
Schiff base compounds (substitution along with addition) in different coordination environments. These complexes were characterized
by elemental analysis, IR and NMR (1H and 13C) spectral studies. The ligand was found to bifunctional tridentate, as well as monodentate for different starting materials
of metal (Sb/Bi), as well as for different reaction conditions, hence, suitable coordination environments and pseudotrigonal
bipyramidal geometry for the antimony and bismuth complexes have been proposed. Their biological activities have also been
checked against many fungi and bacteria. The complexes were found to be more toxic than the corresponding ligand. The article
is published in the original.
The article is published in the original. 相似文献
19.
Seikh Jasimuddin 《Transition Metal Chemistry》2006,31(6):724-729
Dechlorination of M(RaaiR′)
n
Cl2 by AgNO3 produced [M(RaaiR′)
n
(MeCN)2]+2 [M = Ru(II), n = 2; Pt(II), n = 1; RaaiR′ = 1-alkyl-2-(arylazo)imidazole)] which upon reaction with the nucleobase cytosine (C) in MeCN solution gave cytosinato
bridged dimeric compounds which were isolated as perchlorate salts [M2(RaaiR′)
n
(C)2](ClO4)2 · H2O. The products were characterized by IR, u.v.–vis., 1H-n.m.r. spectroscopy and cyclic voltammetry. In MeCN solution the ruthenium complexes exhibit a strong MLCT band at 550–555 nm
and two redox couples positive to SCE due to two metal-center oxidation along with ligand reduction, negative to SCE. The
platinum complexes show a weak transition at 500–520 nm in MeCN and exhibit only ligand reduction in cyclic voltammetry. The
coordination of the ligand was supported by 1H-n.m.r. spectral data. 相似文献
20.
Homo‐ and Heteronuclear Compounds with a Symmetrical Bis‐hydrazone Ligand: Synthesis,Structural Studies,and Luminescent Properties
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Dr. Sabina Rodríguez‐Hermida Dr. Ana B. Lago Prof. Rosa Carballo Dr. Oscar Fabelo Prof. Ezequiel M. Vázquez‐López 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6605-6616
Nine new coordination compounds have been synthesized by the reaction of salts of bivalent metal ions (a=ZnII, b=CuII, c=NiII, d=CoII) with the bis(benzoylhydrazone) derivative of 4,6‐diacetylresorcinol (H4L). Three kinds of complexes have been obtained: homodinuclear compounds [M2(H2L)2]?nH2O ( 1 a , 1 b , 1 c , and 1 d ), homotetranuclear compounds [M4(L)2]?n(solv) ( 2 a and 2 c ), and heterotetranuclear compounds [Zn2M2(L)2]?n(solv) ( 2 ab , 2 ac , and 2 ad ). The structures of the free ligand H4L?2 DMSO and its complexes [Zn2(H2L)2(DMSO)2] ( 1 a* ), [Zn4(L)2(DMSO)6] ( 2 a* ), and [Zn0.45Cu3.55(L)2(DMSO)6]?2 DMSO ( 2 ab* ) were elucidated by single‐crystal X‐ray diffraction. The ligand shows luminescence properties and its fluorimetric behavior towards MII metals (M=Zn, Cu, Ni and Co) has been studied. Furthermore, the solid‐state luminescence properties of the ligand and compounds have been determined at room temperature. 1H NMR spectroscopic monitoring of the reaction of H4L with ZnII showed the deprotonation sequence of the OH/NH groups upon metal coordination. Heteronuclear reactions have also been monitored by using ESI‐MS and spectrofluorimetric techniques. 相似文献