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1.
Dalton Trans ; 45(23): 9419-28, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-26918248

RESUMO

Triorganobismuthines R(C6F5)2Bi (1) and R[2,4,6-(C6F5)3C6H2]2Bi (2) [R = 2-(Me2NCH2)C6H4] were synthesized by reaction of RBiBr2 with C6F5MgBr and 2,4,6-(C6F5)3C6H2Li, respectively, in a 1 : 2 molar ratio. The Bi-chiral bromides R(C6F5)BiBr (3), R(Mes)BiBr (4), and R(Ph)BiBr (5) were obtained from RBiBr2 and C6F5MgBr, MesMgBr or PhMgBr, or from PhBiBr2 and RLi, in a 1 : 1 molar ratio. The molecular structures of 1-5 were determined by single-crystal X-ray diffraction and are discussed taking into account the chirality of the species. Supramolecular aspects in the solid state are presented. The solution behaviour of the title compounds, including dynamic aspects, are discussed on the basis of multinuclear ((1)H, (13)C, (19)F) NMR spectroscopy.

2.
Dalton Trans ; 42(4): 1144-58, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23184021

RESUMO

The reaction of 2-(RN=CH)C(6)H(4)MgBr [R = 2',4',6'-Me(3)C(6)H(2) (R(1)), 2',6'-(i)Pr(2)C(6)H(3) (R(2))] [prepared from 2-(R(1)N=CH)C(6)H(4)Br (1) or 2-(R(2)N=CH)C(6)H(4)Br (2) and Mg] with SbCl(3) in a 2 : 1 and 1 : 1 molar ratio followed by treatment with an aqueous KBr solution gave [2-(R(1)N=CH)C(6)H(4)](2)SbBr (3) and [2-(R(2)N=CH)C(6)H(4)](2)SbBr (4) as well as [2-(R(1)N=CH)C(6)H(4)]SbBr(2) (6) and [2-(R(2)N=CH)C(6)H(4)]SbBr(2) (7). Treatment of 4 with Na(2)S·9H(2)O provided the dinuclear [{2-(R(2)N=CH)C(6)H(4)}(2)Sb](2)S (5). Heterocyclic species, i.e. the oxide cyclo-[{2-(R(2)N=CH)C(6)H(4)}SbO](3) (8) and the sulfides cyclo-[{2-(R(1)N=CH)C(6)H(4)}SbS](2) (9) and cyclo-[{2-(R(2)N=CH)C(6)H(4)}SbS](2) (10), were obtained by reacting dibromides 6 and 7 with KOH and Na(2)S·9H(2)O, respectively, in a water-toluene solvent mixture. The sulfide 10 reacted with [W(CO)(5)(thf)] to yield the heterometallic complex cyclo-[{2-(R(2)N=CH)C(6)H(4)}SbS](2)[W(CO)(5)] (11). The compounds were characterised by multinuclear NMR spectroscopy in solution, mass spectrometry and IR spectroscopy in the solid state. The molecular structures of 4, 5, 6·CHCl(3), 7, 9·CH(2)Cl(2), 10 and 11·0.25CH(3)OH were established by single-crystal X-ray diffraction. Theoretical calculations using DFT methods were carried out on bromide 7 and the geometrical isomers of its dimer association as well as the geometrical isomers of sulfide 10 and its monomer.

3.
J Am Soc Mass Spectrom ; 24(1): 164-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23250666

RESUMO

Reactions of (norbornadiene)Cr(CO)(4) or cis-(piperidine)(2)Mo(CO)(4) with R(2)Sb-SbR(2), and cyclo-(R'Sb)(n) (R' = Et, n-Pr; n = 4, 5) give the complexes cyclo-[M(CO)(4)(R(2)Sb-SbR'- SbR'-SbR(2))] (1: M = Cr, R = Me, R'= Et; 2: M = Mo, R = Et, R' = Et; 3: M = Mo, R = Et, R' = n-Pr). Not accessible to established characterization methods, the oily, extremely reactive unpurified mixture of 3 with scrambled ligands was characterized by mass spectrometry using liquid injection field desorption ionization (LIFDI).

4.
Inorg Chem ; 51(21): 12015-22, 2012 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-23094716

RESUMO

Three discrete organoantimony(III)-containing heteropolytungstates [(PhSb(III))(4)(A-α-Ge(IV)W(9)O(34))(2)](12-) (1), [(PhSb(III))(4)(A-α-P(V)W(9)O(34))(2)](10-) (2), and [{2-(Me(2)NCH(2)C(6)H(4))Sb(III)}(3)(B-α-As(III)W(9)O(33))](3-) (3) have been synthesized in one-pot reactions in aqueous medium using the appropriate lacunary heteropolyanion precursor and organoantimony(III) source. Polyanions 1-3 were isolated as hydrated salts, (NH(4))(12)[(PhSb(III))(4)(A-α-Ge(IV)W(9)O(34))(2)]·20H(2)O (1a), Rb(9)Na[(PhSb(III))(4)(A-α-P(V)W(9)O(34))(2)]·20H(2)O (2a), and Rb(3)[{2-(Me(2)NCH(2)C(6)H(4))Sb(III)}(3)(B-α-As(III)W(9)O(33))]·7H(2)O (3a). The compounds 1a-3a were fully characterized in the solid state using infrared (IR) spectroscopy, single-crystal XRD, and thermogravimetric and elemental analyses. The stability of 1-3 in aqueous solution was confirmed by multinuclear NMR ((1)H, (13)C, (31)P, and (183)W) spectroscopy. Preliminary studies on the biological activity of 1-3 showed that all three compounds might act as potent antimicrobial agents.


Assuntos
Antibacterianos/química , Antimônio/química , Compostos Organometálicos/química , Compostos de Tungstênio/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antimônio/farmacologia , Bacillus subtilis/efeitos dos fármacos , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Espectrofotometria Infravermelho , Termogravimetria , Compostos de Tungstênio/síntese química , Compostos de Tungstênio/farmacologia
5.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): m153-4, 2011 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21522836

RESUMO

The mol-ecular structure of the title compound, [Bi(2)(C(11)H(16)N)(4)(CO(3))], consists of a symmetrically bridging carbonato group which binds two [2-Et(2)NCH(2)C(6)H(4)](2)Bi units that are crystallographically related via a twofold rotation axis bis-ecting the carbonate group. The two Bi atoms and two of the C atoms directly bonded to bis-muth are quasi-planar [deviations of 0.323 (1) and 0.330 (9)Å for the Bi and C atoms, respectively] with the carbonate group. The remaining two ligands are in a trans arrangement relative to the quasi-planar (CBi)(2)CO(3) system. The metal atom is strongly coordinated by the N atom of one pendant arm [Bi-N = 2.739 (6) Å], almost trans to the O atom, while the N atom of the other pendant arm exhibits a weaker intra-molecular inter-action [Bi⋯N = 3.659 (7) Å] almost trans to a C atom. If both these intra-molecular N→Bi inter-actions per metal atom are considered, the overall coordination geometry at bis-muth becomes distorted square-pyramidal [(C,N)(2)BiO cores] and the compound can be described as a hypervalent 12-Bi-5 species. Additional quite short intra-molecular Bi⋯O inter-actions are also present [3.796 (8)-4.020 (9) Å]. Inter-molecular associations through weak η(6)⋯Bi inter-actions [Bi⋯centroid of benzene ring = 3.659 (1) Å] lead to a ribbon-like supra-molecular association.

6.
Dalton Trans ; 39(46): 11277-84, 2010 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-20978674

RESUMO

The reaction of RBiCl(2) (1) [R = 2,6-(Me(2)NCH(2))(2)C(6)H(3)] with Na(2)CO(3) or Ag(2)SO(4) (1 : 1 molar ratio) gave RBiCO(3) (2) and RBiSO(4) (3), respectively. RBi(NO(3))(2) (4) was obtained from RBiCl(2) and AgNO(3) (1 : 2 molar ratio). The ionic complex [R(2)Bi][W(CO)(5)Cl] (6) was obtained from R(2)BiCl (5) and W(CO)(5)(THF), following an unusual chlorine transfer from bismuth to tungsten. Compounds 2-4 are partially soluble in water. The molecular structures of 2·0.5CH(2)Cl(2), 3, 4·H(2)O and 6 were established by single-crystal X-ray diffraction. The carbonate 2 and the sulfate 3 exhibit a polymeric structure based on bridging oxo anions, while for the compound 4 dimer associations are formed, with both bridging and terminal nitrate anions. Dimer associations, based on weak Cl···H interactions between the cation and the anion, were found in the crystal of 6.

7.
Dalton Trans ; 39(28): 6410-8, 2010 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-20454744

RESUMO

Hypervalent organoantimony(III) compounds of the type [2-(Me2NCH2)C6H4]PhSbCl (1), [2-(Me2NCH2)C6H4]MesSbBr (7) and [2-(Me2NCH2)C6H4]nAr(3-n)Sb [n = 1, Ar = Ph (4), Mes (9); n = 2, Ar = Ph (5), Mes (10)] were prepared via salt elimination reactions between [2-(Me2NCH2)C6H4]Li and MesMgBr and PhnSbCl(3-n), [2-(Me2NCH2)C6H4]SbBr2 or [2-(Me2NCH2)C6H4]nSbCl(3-n) (n = 1, 2), in appropriate molar ratios. Halogen exchange reactions with aqueous KBr or KI gave [2-(Me2NCH2)C6H4]ArSbX [Ar = Ph, X = Br (2), I (3); Ar = Mes, X = I (8)]. Metathesis reaction between 1 and MesMgBr affords [2-(Me2NCH2)C6H4]PhMesSb (6). Compounds 1-10 were investigated by means of NMR (1H, 13C) in solution and by mass spectrometry. The investigation of the molecular structures of 2-8 by single-crystal X-ray diffraction revealed that the nitrogen atoms of the pendant CH2NMe2 arms are strongly coordinated to the antimony atoms. All compounds exhibit chirality and crystallize as racemic mixtures.

8.
Dalton Trans ; (26): 5065-7, 2009 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-19562162

RESUMO

The formation and crystal structure of [(Cp2Ti)2(SbR2)2] (1, R=Et), [(Cp2Ti)3(SbR)3Sb] [2, R=2-(Me2NCH2)C6H4], and [(Cp2Ti)5(SbR)2Sb7] (3, R=Me3SiCH2) is reported.

9.
Dalton Trans ; (1): 77-84, 2009 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-19081974

RESUMO

The reaction of RLi [R = 2,6-{MeN(CH2CH2)2NCH2}2C6H3 ] with BiCl3 (1:1 molar ratio) afforded RBiCl2 (2). RBiBr2 (3) and RBiI2 (4) were obtained by halogen-exchange reactions from 2 . The organobismuth(III) dihalides containing the new steric demanding (N,C,N)-pincer ligand were characterized both in solution and solid state. The molecular structures of compounds were established by single-crystal X-ray diffraction. They all show a T-shaped CBiX(2) core, stabilized by two strong intramolecular N-->Bi interactions in trans positions to each other. The overall (N,C,N)BiX2 core exhibits a distorted square-pyramidal coordination geometry. The NMR studies provided evidences for the presence of internal nitrogen-bismuth coordination in solution too. DFT calculations were performed on the related species [2,6-(R(2)NCH(2))(2)C(6)H(3)]BiX(2) (R = H, Me; X = Cl, Br, I) in order to elucidate the bond nature and vibrational spectroscopic features of these compounds.


Assuntos
Bismuto/química , Cristalografia por Raios X/métodos , Halogênios/química , Espectroscopia de Ressonância Magnética/métodos , Compostos Organometálicos/química , Ligantes , Modelos Moleculares , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Dalton Trans ; (14): 1831-42, 2008 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-18369489

RESUMO

R2BiOH (1) [R = 2-(Me2NCH2)C6H4] and (R2Bi)2O (2) are formed by hydrolysis of R2BiCl with KOH. Single crystals of were obtained by air oxidation of (R2Bi)2. The reaction of R2BiCl and Na2CO3 leads to (R2Bi)2CO3 (3). 3 is also formed by the absorption of CO2 from the air in solutions of 1 or 2 in diethyl ether or toluene. (R2Bi)2S (4) is obtained from R2BiCl and Na2S or from (R2Bi)2 and S8. Exchange reactions between R2BiCl and KBr or NaI give R2BiX [X = Br (5), I (6)]. The reaction of RBiCl2 (7) with Na2S and [W(CO)5(THF)] gives cyclo-(RBiS)2[W(CO)5]2 (8). cyclo-(R'BiS)2 (9) [R' = 2,6-(Me2NCH2)2C6H3] is formed by reaction of R'BiCl2 and Na2S. The structures of were determined by single-crystal X-ray diffraction.


Assuntos
Bismuto/química , Carbonatos/química , Calcogênios/química , Halogênios/química , Compostos Organometálicos/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química
11.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): o1585, 2008 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-21203283

RESUMO

The ions of the title chloro-form-solvated salt, C(11)H(17)N(2) (+)·Cl(-)·CHCl(3), are linked by a strong N-H⋯Cl hydrogen bond; the solvent mol-ecule also inter-acts with the chloride ion through a C-H⋯Cl hydrogen bond. Additionally, neighboring cations form weak hydrogen bonds to the anion, resulting in a supra-molecular ribbon that runs along the a axis.

12.
Inorg Chem ; 45(5): 2341-6, 2006 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-16499401

RESUMO

R2Bi-BiR2 [1; R = 2,6-(Me2NCH2)2C6H3], a dibismuthane that exists in different forms in the crystalline state, reacts in air with the formation of the peroxide [R(2)Bi]2(O2) (2) and partial oxidation of the pendant (dimethylamino)methyl groups, yielding the mononuclear bismuth complex R'R' 'Bi (3) [R' = 2-(Me2NCH2)-6-{Me2N(O)CH2}C6H3; R' ' = 2-(Me2NCH2)-6-{O(O)C}C6H3].

13.
Dalton Trans ; (21): 3575-85, 2004 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-15510279

RESUMO

The cyclostibane R(4)Sb(4)(1)(R = 2-(Me(2)NCH(2))C(6)H(4)) was synthesized by reduction of RSbCl(2) with Mg in THF or with Na in liquid NH(3). The reaction of 1 with [W(CO)(5)(THF)] gives the stibinidene complex RSb[W(CO)(5)](2)(2). RSbCl(2) and (RSbCl)(2)E [E = O (6), E = S (8)] react with KOH or Na(2)S in toluene/water to give the heterocycles (RSbE)(n)[E = O, n= 3 (3); E = S, n= 2 (4)]. The chalcogeno-bridged compounds of the type (RSbCl)(2)E [E = O (6), E = S (8)] were synthesized by reaction of RSbCl(2) with KOH or Na(2)S in toluene/water, but also by reaction of RSbCl(2) with the heterocycles (RSbE)(n). The compounds (RSbI)(2)O (7) and (RSbBr)(2)S (9) were prepared via halogen-exchange reactions between (RSbCl)(2)E and NaI (E = O) or KBr (E = S) or by reactions between RSbI(2) and KOH or RSbBr(2) and Na(2)S. The reaction of cyclo-(RSbS)(2) with W(CO)(5)(THF) in THF results in trapping of the cis isomer in cyclo-(RSbS)(2)[W(CO)(5)](5). The solution behaviour of the compounds was investigated by (1)H and (13)C NMR spectroscopy. The molecular structures of compounds 1-7 and 9 were determined by single-crystal X-ray diffraction.

14.
Inorg Chem ; 42(5): 1751-7, 2003 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-12611549

RESUMO

RR'SbCl (1) and RR'BiCl (2) [R = 2-(Me(2)NCH(2))C(6)H(4), R' = CH(Me(3)Si)(2)] form by the reaction of R'ECl(2) (E = Sb, Bi) with RLi. The reaction of 1 with LiAlH(4) and metalation with n-BuLi gives RR'SbH (3) and RR'SbLi.2THF (4) (THF = tetrahydrofuran). Transmetalation of 4 with sodium tert-butoxide in the presence of TMEDA (TMEDA = tetramethylethylenediamine) leads to RR'SbNa.TMEDA (5). Structural analyses by (1)H NMR in C(6)D(6), C(6)D(5)CD(3), or (CD(3))(2)SO with a variation of the temperature (1, 2, 4, and 5) and by single-crystal X-ray diffraction (1, 2, 4, and 5) revealed the intramolecular coordination of the pendant Me(2)N group on the pnicogen centers in 1 and 2 and on Li or Na in 4 or 5. The variable-temperature (1)H NMR spectra of the hydride 3 in C(6)D(6), C(6)D(5)CD(3), or (CD(3))(2)SO show that the pyramidal configuration on antimony is stable up to 100 degrees C, whereas inversion at the nitrogen is not prevented by internal coordination even at -80 degrees C. The crystals of 1, 2, 4, and 5 consist of discrete molecules with the Sb and Bi atoms in an approximately Psi-trigonal-bipyramidal environment in the cases of 1 and 2 and in a pyramidal environment in the cases of 4 and 5. Crystal data for 1: triclinic, space group Ponemacr;, a = 7.243(4) A, b = 10.373(3) A, c = 15.396(5) A, alpha = 79.88 degrees, beta = 78.27 degrees, gamma = 71.480(10) degrees, V = 1066.2(7) A(3), Z = 2, R = 0.0614. 2: monoclinic, space group P2(1)/n, a = 10.665(2) A, b = 14.241(2) A, c = 14.058(2) A, beta = 90.100(10) degrees, V = 2135.1(6) A(3), Z = 4, R = 0.049. 4: monoclinic, space group P2(1)/n, a = 11.552(2) A, b = 16.518(3) A, c = 15.971(5) A, beta = 96.11(2) degrees, V = 3030.2(12) A(3), Z = 4, R = 0.0595. 5: monoclinic, space group P2(1)/n, a = 9.797(2) A, b = 24.991(5) A, c = 14.348(3) A, beta = 94.98(3) degrees, V = 3499.66(12) A(3), Z = 4, R = 0.0571. The dissociation of the intramolecular N-pnicogen bond and inversion at the nitrogen occurs when solutions of 1 or 2 in C(6)D(6) or C(6)D(5)CD(3) are heated above 25 or 30 degrees C. 1 and 3-5 are stable with respect to inversion of the configuration at the antimony in C(6)D(6), C(6)D(5)CD(3), or (CD(3))(2)SO up to 160 degrees C. Bismuth inversion, probably via the edge mechanism, is observed in solutions of 2 in (CD(3))(2)SO at 45 degrees C but not in C(6)D(5)CD(3) below 125 degrees C.

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