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1.
Tris(iso‐propyl)stibine complexes of palladium and platinum of the type [MX2(SbiPr3)2] [M, X = Pd, Cl (1a), Pd, Br (1b), Pd, I (1c), Pt, Cl (2)] have been prepared and characterized by elemental analysis, IR and 1H NMR spectral data. The structure of 1a, established by X‐ray structural analysis, revealed that the palladium atom is in a square planar environment with mutually trans SbiPr3 ligands. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
2.
《Journal of Coordination Chemistry》2012,65(10):1750-1764
Reactions of copper(I) halides with triphenyl phosphine in acetonitrile followed by the addition of salicylaldehyde N-ethylthiosemicarbazone {(2-OH–C6H4)(H)C2=N3–N2H–C1(=S)N1HEt, H2stsc-NEt} in chloroform in 1?:?2?:?1 (Cl) or 1?:?1?:?1 (Br, I) molar ratios yield mononuclear, [CuCl(η 1-S-H2stsc-NHEt)(PPh3)2] (1) and sulfur-bridged dinuclear, [Cu2X2(μ-S-H2stsc-NEt)2(PPh3)2] (X?=?Br, 4; I, 5) complexes. Similarly, reaction of silver halides (Cl, Br) with H2stsc-NEt in acetonitrile followed by the addition of PPh3 to the solid that formed (1?:?1?:?2 molar ratio), yielding mononuclear complexes, [AgX(η 1-S-H2stsc-NHEt)(PPh3)2] (Cl, 2; Br, 3). All these complexes are characterized with analytical data, IR, and NMR spectroscopy and single-crystal X-ray crystallography. The ligand favored η 1-S bonding in 1, 2, and 3, and μ-S bonding in 4 and 5. Cu?···?Cu contacts were 3.063?Å. The complexes form 1-D or 2-D H-bonded networks, entrapping solvent in some cases. 相似文献
3.
Imidazolium salts bearing triazole groups are synthesized via a copper catalyzed click reaction, and the silver, palladium, and platinum complexes of their N‐heterocyclic carbenes are studied. [Ag4(L1)4](PF6)4, [Pd(L1)Cl](PF6), [Pt(L1)Cl](PF6) (L1=3‐((1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)methyl)‐1‐(pyrimidin‐2‐yl)‐1H‐imidazolylidene), [Pd2(L2)2Cl2](PF6)2, and [Pd(L2)2](PF6)2 (L2=1‐butyl‐3‐((1‐(pyridin‐2‐yl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)imidazolylidene) have been synthesized and fully characterized by NMR, elemental analysis, and X‐ray crystallography. The silver complex [Ag4(L1)4](PF6)4 consists of a Ag4 zigzag chain. The complexes [Pd(L1)Cl](PF6) and [Pt(L1)Cl](PF6), containing a nonsymmetrical NCN ′ pincer ligand, are square planar with a chloride trans to the carbene donor. [Pd2(L2)2Cl2](PF6)2 consists of two palladium centers with CN2Cl coordination mode, whereas the palladium in [Pd(L2)2](PF6)2 is surrounded by two carbene and two triazole groups with two uncoordinated pyridines. The palladium compounds are highly active for Suzuki–Miyaura cross coupling reactions of aryl bromides and 1,1‐dibromo‐1‐alkenes in neat water under an air atmosphere. 相似文献
4.
Filippou AC Chernov O Schnakenburg G 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(48):13574-13583
An efficient method for the synthesis of the first N‐heterocyclic carbene (NHC)‐stabilized halosilylidyne complexes is reported that starts from SiBr4. In the first step, SiBr4 was treated with one equivalent of the N‐heterocyclic carbene 1,3‐bis[2,6‐bis(isopropyl)phenyl]imidazolidin‐2‐ylidene (SIdipp) to give the 4,5‐dihydroimidazolium salt [SiBr3(SIdipp)]Br ( 1‐Br ), which then was reduced with potassium graphite to afford the silicon(II) dibromide–NHC adduct SiBr2(SIdipp) ( 2‐Br ) in good yields. Heating 2‐Br with Li[CpCr(CO)3] afforded the complex [Cp(CO)2Cr?SiBr(SIdipp)] ( 3‐Br ) upon elimination of CO. Complex 3‐Br features a trigonal‐planar‐coordinated silicon center and a very short Cr?Si double bond. Similarly, the reaction of SiCl2(SIdipp) ( 2‐Cl ) with Li[CpCr(CO)3] gave the analogous chloro derivative [Cp(CO)2Cr?SiCl(SIdipp)] ( 3‐Cl ). Complex 3‐Br undergoes an NHC exchange with 1,3‐dihydro‐4,5‐dimethyl‐1,3‐bis(isopropyl)‐2H‐imidazol‐2‐ylidene (IMe2iPr2) to give the complex [Cp(CO)2CrSiBr(IMe2iPr2)2] ( 4‐Br ). Compound 4‐Br features a distorted‐tetrahedral four‐coordinate silicon center. Bromide abstraction occurs readily from 4‐Br with Li[B(C6F5)4] to give the putative silylidene complex salt [Cp(CO)2Cr?Si(IMe2iPr2)2][B(C6F5)4], which irreversibly dimerizes by means of an Si‐promoted electrophilic activation of one carbonyl oxygen atom to yield the dinuclear siloxycarbyne complex [Cp(CO)Cr{(μ‐CO)Si(IMe2iPr2)2}2‐ Cr(CO)Cp][B(C6F5)4]2 ( 5 ). All compounds were fully characterized, and the molecular structures of 2‐Br – 5‐Br were determined by single‐crystal X‐ray diffraction. DFT calculations of 3‐Br and 3‐Cl and their carbene dissociation products [Cp(CO)2Cr?Si? X] (X=Cl, Br) were carried out, and the electronic structures of 3‐Br , 3‐Cl and [Cp(CO)2Cr?Si? X] were analyzed by the natural bond orbital method in combination with natural resonance theory. 相似文献
5.
Ivan J. B. Lin 《中国化学会会志》1983,30(1):17-20
Some halo or mercaptide bridged palladium (II) dimers, [Pd(S2CNR2)X]3 (R=ibutyl, X=Cl, Br, I, S-ethyl and S-t-butyl) were studied by variable temperature 1H nmr spectroscopy. Line shape changes of the chloro and bromo bridged dimers were interpretated by the solvolytic breaking of the Pd-X bond, while mercaptide bridged complexes were explained in terms of slow N-C single bond rotation. The results consist with the strengthness of the class b metal ion with various soft donor ligands. 相似文献
6.
《Journal of Coordination Chemistry》2012,65(3-4):209-216
Abstract By reaction of palladium halides with D,L-ethionine (D,L-EthH; molar ratio 1:1) in dichloromethane solutions containing an excess of 2,6-dimethyl-4H-pyran-4-one (DMP) [Pd(D,L-EthH)X2] (X?Cl, Br or I) complexes have been isolated. When the solvent was benzene [Pd(D,L-EthH)X2].DMP adducts were obtained in which the DMP molecule does not bind to the metal. The complexes have been characterized by infrared and nmr (1H and 13C) spectroscopy and by thermogravimetric measurements (TG, DTG and DTA). The importance of DMP in determining the reaction course is discussed. 相似文献
7.
Summary The compounds EtO2CCH2(Me)NCS2R (R = Me, ESDTM; R = Et, ESDTE) were prepared from sarcosine ethyl ester hydrochloride, CS2 and alkyl iodide in EtOH-H2O. These ligands react with palladium halides in benzene to yield the benzene solvates [Pd(ESDTR)X2]·nC6H6 (R = Me or Et; X = Cl or Br; n < 1), in which the dithioester molecule coordinates through both sulphur atoms. Ligands and complexes have been characterized
by i.r. and 1H n.m.r. spectroscopy and by thermal analysis (t.g., d.t.g. and d.t.a.). The low stability of the adducts in both solution
and solid phase is discussed on the basis of proton n.m.r. spectra. Thermal degradation of the 1∶1 complexes has been examined
up to 1000° C. The first decomposition step involves release of alkyl halide to form the [Pd(ESDT)X]
n
(X = Cl or Br) intermediates, which successively decompose, finally giving palladium. 相似文献
8.
Bridged N,N′-substituted bisbenzimidazolium bromide salts (L1, L2, and L3) were synthesized and fully characterized. Reactions of palladium acetate with L1, L2, and L3 afforded corresponding new bridged bis(N-heterocyclic carbene)palladium(II) complexes (C1, C2, and C3) in high yields. The X-ray structure of complex C1 showed that the Pd(II) ion is bonded to the two carbon atoms of the bis(N-heterocyclic carbene) and two bromido ligands are in the cis position, resulting in a distorted square planar geometry. The three Pd(NHC)2Br2 complexes C1, C2, and C3 were evaluated in carbonylative Suzuki–Miyaura coupling reactions of aryl boronic acids with aryl halides and displayed high catalytic activity with low catalyst loading. The coupling reactions of aryl bromides were selective towards the carbonylation product at higher carbon monoxide pressure. 相似文献
9.
Magno Agostinho Andrei Banu Pierre Braunstein Richard Welter Xavier Morise 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(3):m81-m86
Three new palladium complexes containing a difunctional P,N‐chelate, namely tris(chloro{[1‐methyl‐1‐(6‐methyl‐2‐pyridyl)ethoxy]diphenylphospine‐κ2N,P}methylpalladium(II)chloroform solvate, 3[Pd(CH3)Cl(C21H22NOP)]·CHCl3, (III), dichloro[2‐(2,6‐dimethylphenyl)‐6‐(diphenylphosphinomethyl)pyridine‐κ2N,P]palladium(II), [PdCl2(C26H24NP)], (IV), and chloro[2‐(2,6‐dimethylphenyl)‐6‐(diphenylphosphinomethyl)pyridine‐κ2N,P]methylpalladium(II), [Pd(CH3)Cl(C26H24NP)], (V), are reported. Geometric data and the conformations of the ligands around the metal centers, as well as slight distortions of the Pd coordination environments from idealized square‐planar geometry, are discussed and compared with the situations in related compounds. Non‐conventional hydrogen‐bond interactions (C—H⋯Cl) have been found in all three complexes. Compound (III) is the first six‐membered chloro–methyl–phosphinite P,N‐type PdII complex to be structurally characterized. 相似文献
10.
Parasuraman Karthikeyan Prashant Narayan Muskawar Sachin Arunrao Aswar Pundlik Rambhau Bhagat Suresh Kumar Sythana 《应用有机金属化学》2012,26(11):562-569
A novel, effective 1‐glycyl‐3‐methyl imidazolium chloride–palladium(II) complex ([Gmim]Cl–Pd(II)) was synthesized and studied as an organocatalyst for the Sonogashira coupling reaction under solvent‐free conditions at 25 °C. The hydrophobic group on amino acid favors reagent diffusion toward the chloroglycine moiety, increasing the catalytic activity of supported palladium complex. By this protocol, different aryl halides (Cl, Br and I) were reacted with phenylacetylene in good to excellent yields with turnover number 8.0 × 102 to 9.6 × 102. The catalyst was recycled for the reaction of bromobenzene with phenylacetylene for eight runs without appreciable loss of its catalytic activity and negligible metal leaching. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
11.
Yue-Qing Zheng Horst Borrmann Yuri Grin Karl Peters Hans Georg von Schnering 《无机化学与普通化学杂志》1999,625(12):2115-2119
The reaction of W6Br12 with AgBr in evacuated silica tubes (temperature gradient 925 K/915 K) yielded brownish black octahedra of Ag[W6Br14] ( I ) and yellowish green platelets of Ag2[W6Br14] ( II ) both in the low temperature zone. ( I ) crystallizes cubically (Pn3 (no. 201); a = 13.355 Å, Z = 4) and ( II ) monoclinically (P21/c (no. 14); a = 9.384 Å, b = 15.383 Å, c = 9.522 Å, β = 117.34°, Z = 2). Both crystal structures contain isolated cluster anions, namely [(W6Bri8)Bra6]1– and [(W6Bri8)Bra6])]2–, respectively, with the mean distances and angles: ( I ) d(W–W) = 2.648 Å, d(W–Bri) = 2.617 Å, d(W–Bra) = 2.575 Å, d(Bri…Bri) = 3.700 Å, d(Bri…Bra) = 3.692 Å, ∠W–Bri–W = 60.78°. ( II ) d(W–W) = 2.633 Å, d(W–Bri) = 2.624 Å, d(W–Bra) = 2.613 Å, d(Bri…Bri) = 3.710 Å, d(Bri…Bra) = 3.707 Å, ∠W–Bri–W = 60.23°. The Ag+ cations are trigonal antiprismatically coordinated in ( I ) with d(Ag–Br) = 2.855 Å, but distorted trigonally planar in ( II ) with d(Ag–Br) = 2.588–2.672 Å. The structural details of hitherto known compounds with [W6Br14] anions will be discussed. 相似文献
12.
An analysis of thermochemical and kinetic data on the bromination of the halomethanes CH4–nXn (X = F, Cl, Br; n = 1–3), the two chlorofluoromethanes, CH2FCl and CHFCl2, and CH4, shows that the recently reported heats of formation of the radicals CH2Cl, CHCl2, CHBr2, and CFCl2, and the C? H bond dissociation energies in the matching halomethanes are not compatible with the activation energies for the corresponding reverse reactions. From the observed trends in CH4 and the other halomethanes, the following revised ΔH°f,298 (R) values have been derived: ΔH°f(CH2Cl) = 29.1 ± 1.0, ΔH°f(CHCl2) = 23.5 ± 1.2, ΔHf(CH2Br) = 40.4 ± 1.0, ΔH°f(CHBr2) = 45.0 ± 2.2, and ΔH°f(CFCl2) = ?21.3 ± 2.4 kcal mol?1. The previously unavailable radical heat of formation, ΔH°f(CHFCl) = ?14.5 ± 2.4 kcal mol?1 has also been deduced. These values are used with the heats of formation of the parent compounds from the literature to evaluate C? H and C? X bond dissociation energies in CH3Cl, CH2Cl2, CH3Br, CH2Br2, CH2FCl, and CHFCl2. 相似文献
13.
Abstract: Two new lead azide halides, PbN3X (X = Cl, Br), were precipitated from aqueous solutions and structurally analyzed by both X-ray single-crystal/powder diffraction and vibrational spectroscopy, in addition to density-functional theory calculations. PbN3Cl crystallizes in the monoclinic space group P21/m (no. 11) with a = 5.5039(11), b = 4.3270(9), c = 7.6576(15) Å, β = 101.28(3)° and adopts a structure with alternating layers of cations and anions. PbN3Br crystallizes in the orthorhombic space group Pnma (no. 62) with a = 7.9192(2), b = 4.2645(1), c = 11.1396(3) Å, and the cations and anions are alternating crosswise. Within PbN3Cl, a Pb2+ cation is surrounded by five azide and four chloride anions whereas, in PbN3Br, the coordination consists of five azide and three bromide anions. Both structures contain chain-like [Pb2X2]2+ units with Pb–Cl = 2.95–3.21 Å and Pb–Br = 3.03–3.38 Å, and the N3– dumbbell is capped by five Pb2+ with Pb–N = 2.79–2.91 Å in PbN3Cl and with Pb–N = 2.69–2.89 Å in PbN3Br. The infrared and Raman spectra show the typical frequencies of a slightly asymmetric N3– unit, in good agreement with DFT phonon calculation. Thermal analyses reveal PbN3Cl to be stable up to 290 °C before it explodes to yield PbCl2, metallic Pb, and gaseous N2. 相似文献
14.
《Journal of Coordination Chemistry》2012,65(20):3233-3249
AbstractDinuclear Pd(II) halides that contain bridging π-conjugated groups, trans,trans-[(PR3)2(X)Pd–Y–Pd(X)(PR3)2] (X?=?Br; YH2 = terpyridine, fluorenone, benzil, benzthiadiazole), were prepared by the oxidative addition of corresponding dihalo π-conjugated reagents to [Pd(styrene)(PR3)2]. Similar reactions involving dihalobenzil, dihalobithiophene, or dihaloterthiophene afforded dinuclear Pt(II) halides containing bridging π-conjugated groups. Additionally, when the dihalosilole derivatives {2,5-dibromo-1,1-dimethyl (or diphenyl)-3,4-diphenylsilole} reacted with [Pd(styrene)(PR3)2], mono or dinuclear Pd(II) complexes bearing a dimethyl (or diphenyl)-3,4-diphenylsilole group were obtained. π-Conjugation extension reactions of dinuclear bithiophene-bridged Pd(II) halides with HC≡C–R {R?=?SiPh3, C(O)OMe} in the presence of CuI and HNEt2 led to the unexpected formation of bis(acetylide) Pd(II) complexes of the form, [Pd(C≡C–R)2(PR3)2] and bithiophene. In contrast, treatment of the dinuclear Pd(II) halides with two equiv of organic isocyanide resulted in isocyanide insertion into the Pd???C bonds to afford π-conjugation-extended dinuclear Pd(II) compounds bearing a π-conjugated moiety. 相似文献
15.
Michael Weigelt Diana Becher Eike Poetsch Clemens Bruhn Dirk Steinborn 《无机化学与普通化学杂志》1999,625(9):1542-1547
On the Oxidative Addition of 1-Halogenalk-1-ynes – Synthesis and Structure of Phenylalkynylpalladium Complexes [Pd(PPh3)4] ( 2 ) reacts with IC≡CPh and ClC≡CPh in the sense of an oxidative addition to give trans-[Pd(C≡CPh)X(PPh3)2] (X = I: 3 a , X = Cl: 3 b ). As side products trans-[PdX2(PPh3)2] (X = I: 4 a , X = Cl: 4 b ; < 10%) and PhC≡C–C≡CPh ( 5 ; X = I: ca 30%, X = Cl: < 4%) are formed. 3 a and 3 b were characterized by NMR (1H, 13C, 31P) and IR spectroscopies as well as by X-ray single-crystal structure analyses. In the crystals of 3 a and 3 b isolated molecules were found. The Pd–C≡C–Ph unit is linear in 3 a and approximately linear in 3 b [Pd–C≡C 174.2(6)°, C≡C–C 179,0(7)°]. 相似文献
16.
Olivier Blacque Dr. Christian M. Frech Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(5):1521-1531
Pincer‐type palladium complexes are among the most active Heck catalysts. Due to their exceptionally high thermal stability and the fact that they contain PdII centers, controversial PdII/PdIV cycles have been often proposed as potential catalytic mechanisms. However, pincer‐type PdIV intermediates have never been experimentally observed, and computational studies to support the proposed PdII/PdIV mechanisms with pincer‐type catalysts have never been carried out. In this computational study the feasibility of potential catalytic cycles involving PdIV intermediates was explored. Density functional calculations were performed on experimentally applied aminophosphine‐, phosphine‐, and phosphite‐based pincer‐type Heck catalysts with styrene and phenyl bromide as substrates and (E)‐stilbene as coupling product. The potential‐energy surfaces were calculated in dimethylformamide (DMF) as solvent and demonstrate that PdII/PdIV mechanisms are thermally accessible and thus a true alternative to formation of palladium nanoparticles. Initial reaction steps of the lowest energy path of the catalytic cycle of the Heck reaction include dissociation of the chloride ligands from the neutral pincer complexes [{2,6‐C6H3(XPR2)2}Pd(Cl)] [X=NH, R=piperidinyl ( 1 a ); X=O, R=piperidinyl ( 1 b ); X=O, R=iPr ( 1 c ); X=CH2, R=iPr ( 1 d )] to yield cationic, three‐coordinate, T‐shaped 14e? palladium intermediates of type [{2,6‐C6H3(XPR2)2}Pd]+ ( 2 ). An alternative reaction path to generate complexes of type 2 (relevant for electron‐poor pincer complexes) includes initial coordination of styrene to 1 to yield styrene adducts [{2,6‐C6H3(XPR2)2}Pd(Cl)(CH2?CHPh)] ( 4 ) and consecutive dissociation of the chloride ligand to yield cationic square‐planar styrene complexes [{2,6‐C6H3(XPR2)2}Pd(CH2?CHPh)]+ ( 6 ) and styrene. Cationic styrene adducts of type 6 were additionally found to be the resting states of the catalytic reaction. However, oxidative addition of phenyl bromide to 2 result in pentacoordinate PdIV complexes of type [{2,6‐C6H3(XPR2)2}Pd(Br)(C6H5)]+ ( 11 ), which subsequently coordinate styrene (in trans position relative to the phenyl unit of the pincer cores) to yield hexacoordinate phenyl styrene complexes [{2,6‐C6H3(XPR2)2}Pd(Br)(C6H5)(CH2?CHPh)]+ ( 12 ). Migration of the phenyl ligand to the olefinic bond gives cationic, pentacoordinate phenylethenyl complexes [{2,6‐C6H3(XPR2)2}Pd(Br)(CHPhCH2Ph)]+ ( 13 ). Subsequent β‐hydride elimination induces direct HBr liberation to yield cationic, square‐planar (E)‐stilbene complexes with general formula [{2,6‐C6H3(XPR2)2}Pd(CHPh?CHPh)]+ ( 14 ). Subsequent liberation of (E)‐stilbene closes the catalytic cycle. 相似文献
17.
《Journal of Coordination Chemistry》2012,65(4):481-484
Dichloro(N,N-diethyl-ethane-1,2-diamine)copper(II) has copper(II) ions in square pyramidal coordination. The two nitrogen atoms of the diamine {Cu–Nprimary?=?1.979(3), Cu–Ntertiary?=?2.108(2)?Å} and two chloride ions are in the basal plane {Cu–Cl1?=?2.2680(9), Cu–Cl2?=?2.2989(8)?Å}. A centrosymmetrical dimer di-μ-chloro-bis{chloro(N,N-diethylethane-1,2-diamine-κ2)copper(II)}, C6H16Cl2CuN2, is formed by axial coordination by Cl2, trans to the tertiary nitrogen, to a second copper(II) ion, with Cu?···?Cui?=?3.4855(9) and Cl2–Cui?=?2.7860(8)?Å. The dimer is also linked by H-bond N1–H?···?Cl1i. 相似文献
18.
Antonio C. Fabretti Gian Carlo Franchini Giorgio Peyronel 《Transition Metal Chemistry》1978,3(1):355-359
Summary The following palladium(II) and platinum(ll) complexes of rhodanine (HRd) and 3-methylrhodanine (MRd) have been prepared: Pd(HRd)1.5Cl2, Pd(HRd)2Br2, Pd(HRd)2Br2 · 0.25 EtOH, M(MRd)2X2 [M = Pd, X = Cl (0.25 EtOH) or Br; M = Pt, X = Cl or Br], Pd(MRd)3Br2, and M(MRd)4(ClO4)2 (M = Pd or Pt). The ligands are coordinated to the metal through the thiocarbonylic sulphur atom. Pd(HRd)1.5Cl2 has presumably a structure such as (X = Cl or Br) complexes have a trans-planar coordination. Pd(MRd)2X2 (X = Cl or Br) complexes arecis-planar coordinated. Pd(MRd)3Br2 has presumably a square coordination with two MRd molecules and two CI ionscis-coordinated in the equatorial plane, and a MRd molecule and a Cl ion weakly bonded in apical position. The M(MRd)4(ClO4)2 complexes have square planar coordination.Author to whom all correspondence should be addressed. 相似文献
19.
Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of trans-(PNP)[TcCl4(Py)2] and trans-(PNP)[TcBr4(Py)2] By reaction of (PNP)2[TcX6] with pyridine in the presence of [BH4]? (PNP)[TcX4(Py)2], X = Cl, Br, are formed. X-ray structure determinations on single crystals of these isotypic TcIII complexes (monoclinic, space group P21/n, Z = 2, for X = Cl: a = 13.676(4), b = 9.102(3), c = 17.144(2) Å, β = 91.159(1)°; for X = Br: a = 13.972(2), b = 9.146(3), c = 17.285(4) Å, β = 90.789(2)°) result in the averaged bond distances Tc? Cl: 2.386, Tc? Br: 2.519, Tc? N: 2.132(3) (X = Cl) and 2.143(4) Å (X = Br). The two pyridine rings are coplanar and vertical to the X? Tc? X-axes, forming angles of 42.28° (X = Cl) and 43.11° (X = Br). Using the molecular parameters of the X-ray structure determination and assuming D2h point symmetry, the IR and Raman spectra are assigned by normal coordinate analysis based on a modified valence force field. Good agreement between observed and calculated frequencies is obtained with the valence force constants fd(TcCl) = 1.45, fd(TcBr) = 1.035, fd(TcN) = 1.37 (X = Cl) and 1.45 mdyn/ Å (X = Br), respectively. 相似文献
20.
G. A. Abakumov V. K. Cherkasov M. P. Bubnov L. G. Abakumova V. N. Ikorskii G. V. Romanenko A. I. Poddel’sky 《Russian Chemical Bulletin》2006,55(1):44-52
New five-coordinate complexes Co(ISQ-Pri)2Cl, Co(ISQ-Me)2Cl, Co(ISQ-Me)2I, Co(ISQ-Me)2(SCN), Mn(ISQ-Pri)2Cl, and Fe(ISQ-Me)2Br (ISQ-Pri and ISQ-Me are the 4,6-di-tert-butyl-N-(2,6-diisopropylphenyl)-and 4,6-di-tert-butyl-N-(2,6-dimethylphenyl)-o-iminobenzosemiquinone radical anions, respectively) were synthesized. The complexes were characterized by UV-Vis and IR spectroscopy
and magnetochemistry. The molecular structures of the Fe(ISQ-Me)2Br and Mn(ISQ-Pri)2Cl complexes were established by X-ray diffraction. The singlet ground state (S = 0) of the cobalt complexes is caused by
antiferromagnetic coupling between the unpaired electrons of the radical ligands (S = 1/2) through the fully occupied atomic orbitals of low-spin cobalt(III) (d6, S = 0). The effective magnetic moments of the complexes at 10 K are 0.18 μB for Co(ISQ-Pri)2Cl and 0.16 μB for Co(ISQ-Me)2I. The ground state of the manganese complex is triplet (S = 1). Two unpaired electrons of the o-iminobenzosemiquinone ligands are strongly antiferromagnetically coupled with two of four unpaired electrons of high-spin
manganese(III) (d4, S = 2).
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 43–51, January, 2006. 相似文献