Crystal Structure Of Trans Research Articles

Coulombic inter-ligand repulsion effects on the Pt(ii) coordination chemistry of oligocationic, ammonium-functionalized triarylphosphines

The Pt(II) coordination chemistry of oligocationic ammoniomethyl- and neutral aminomethyl-substituted triarylphosphines (L) is described. Complexes of the type PtX(2)(L)(2) (X = Cl, I) have been isolated and characterized. For the hexa-meta-ammoniomethyl-substituted ligands [1](6+) and [2](6+), two ligands always occupy a trans-configuration with respect to each other in complexes of the type PtX(2)(L)(2), while for the tri-para-ammoniomethyl-substituted ligand [7](3+), the trans/cis ratio is dependent on the ionic strength of the solution. This behaviour was not observed for the neutral aminomethyl-substituted ligands. In the crystal structure of trans-[PtI(2)(1)(2)]I(12), the geometrical parameters of the phosphine ligand [1](6+) are very similar to those found in the analogous complex of the benchmark ligand PPh(3), i.e. trans-PtI(2)(PPh(3))(2), indicating that no significant increase in the steric congestion is present in the complex. Instead, the coordination chemistry of this class of phosphine ligands is dominated by repulsive Coulombic inter-ligand interactions.

Stabilization of Triam(m)inechloridoplatinum Complexes by Oxidation to PtIV

PtIV analogues of the active end groups {PtClN3} of multinuclear Pt anticancer drugs have been investigated. The crystal structure of trans,mer-[PtCl(OH)2(dien)]Cl shows that the bond lengths are similar to those in the dihydroxidoplatinum(iv) analogue of cisplatin. The axial ligands are shown to be the predominant influence on reduction potentials with the dihydroxido complex trans,mer-[PtCl(OH)2(NH3)3]Cl being the most resistant to reduction. X-ray absorption near-edge spectroscopy is shown to be suitable for monitoring the oxidation state of these complexes and reveals that trans,mer-[PtCl(OH)2(NH3)3]+ survives for more than 2 h in cancer cells.

ChemInform Abstract: Involvement of Iron Alkyl Complexes and Alkyl Radicals in the Kharasch Reactions: Probing the Catalysis Using Iron Phosphine Complexes.

The X-ray crystal structure of trans-[FeBr2(depe)2](depe = Et2PCH2CH2PEt2) has been determined, and its catalysis of the reactions between MgBrEt and RBr (R = Et, Prn, Bun, PhCH2 or H2CCHCH2) to give alkanes and alkenes investigated. Detailed analysis of the products and the time courses of the reactions demonstrate that the hydrido-species trans-[FeH(Br)(depe)2]n+(n= 0 or 1) are not intermediates in the reaction, but are products formed in the termination steps. It is shown that the catalysis can proceed by one of two pathways, depending on the alkyl halide. One pathway is proposed to involve the intermediacy of iron(I) species, and the other of iron(III) complexes. Both catalytic cycles contain the same fundamental reaction: the abstraction of a β-hydrogen atom from a [FeEt(Br)(depe)2]n+ species by alkyl radicals to give the alkane and ethylene. The X-ray crystal structure of trans-[FeH(Br)(depe)2]BPh4 is reported.

Ruthenium(II) 2,2′-bipyridine complexes incorporating substituted phenylazo-(2-(phenylthio))phenylmethine ancillary ligands. Synthesis, crystal structure, spectroscopic and redox properties

AbstractFive ruthenium complexes bearing phenylazo-(2-(phenylthio))phenylmethine ligands of the general type trans-[Ru II (bpy)(L)(Cl) 2 ] (C1-C5) {L = YC 6 H 4 N=NC(COCH 3 )=NC 6 H 4 (2-SC 6 H 5 ), H (L1), Cl (L2), OCH 3 (L3), Br (L4), or NO 2 (L5)} have been synthesized. The crystal structure of trans-[Ru(bpy)(L1)(Cl) 2 ] (C1) is reported and shows no direct metal-S interaction. The complexes have been characterized through spectroscopic (IR, UV/vis and NMR) and electrochemical (CV) techniques. The electrochemical parameters (E L (L)) of the azoimine ligands are reported.Graphical AbstractFive ruthenium complexes bearing phenylazo-(2-(phenylthio))phenylmethine ligands of the general type trans-[Ru II (bpy)(L)(Cl) 2 ] {L = YC 6 H 4 N=NC(COCH 3 )=NC 6 H 4 (2-SC 6 H 5 ), Y = H (L1), Cl (L2), OCH 3 (L3), Br (L4), and NO 2 (L5)} has been synthesized. The crystal structure of the complex trans-[Ru(bpy)(L1)(Cl) 2 ] is reported and show no direct metal-S interactions. This family has been characterized through spectroscopic and electrochemical techniques. The electrochemical parameters (E L (L)) of these new ligands (L) are reported.[IMAGE]

Crystal structure of trans- and cis-bis(acetylacetonato)bis(trimethylphosphite)ruthenium(II) complexes and testing their catalytic activity in hydrogen generation from the hydrolysis of sodium borohydride

Abstract Both the trans and cis isomers of [Ru(acac)2{P(OMe)3}2] were isolated in the form of single crystals and characterized by single crystal X-ray diffraction, UV–Vis, MS, 1H, 13C and 31P NMR spectroscopy. The compounds of ruthenium(II), both mononuclear complexes, crystallize in triclinic P 1 ¯ space group. The metal ion in both compounds has similar, slightly distorted octahedral coordination geometry. Both complexes were tested as catalyst in hydrogen generation from the hydrolysis of sodium borohydride. When used alone, none of the trans- and cis-[Ru(acac)2{P(OMe)3}2] complexes shows significant catalytic activity. However, the catalytic activity of cis-[Ru(acac)2{P(OMe)3}2] in the hydrolysis of sodium borohydride is significantly enhanced by the addition of two equivalents of trimethylphosphite per ruthenium into the medium.

Crystal Structure and Spectroscopic Properties of trans-Dibromobis(1,2-ethanediamine)chromium(III) Perchlorate

The crystal structure of trans-[Cr(en)2Br2]ClO4 (en = 1,2-ethanediamine) has been determined by a single-crystal X-ray diffraction study at 150 K. The complex crystallizes in the space group $$ P\overline{1} $$ of the triclinic system with two mononuclear formula units in a cell of dimensions a = 6.853(4), b = 8.109(5), c = 12.475(8) A, α = 81.006(10)°, β = 77.005(10)° and γ = 74.981(10)°. The Cr atom is in a slightly distorted octahedral environment, coordinated by four nitrogen atoms of two en ligands and two bromine atoms in trans axial positions. The mean Cr–N(en) and Cr–Br bond lengths are 2.079(3) and 2.4743(10)A, respectively. The five-membered rings are in stable gauche conformations with N1–Cr1–N2 and N3–Cr2–N4 angles of 82.81(11)° and 83.67(11)°, respectively. The crystal packing is stabilized by a network of N–H···O and N–H···Br hydrogen bonds. The infrared and electronic absorption spectra are consistent with the results of X-ray crystallography. The spectroscopic properties of the title complex are in good agreement with the result of X-ray crystallography, which shows that the chromium atom is in an octahedral environment, coordinated by two bidentate 1,2-ethanediamine ligands and two bromine atoms in trans positions.

Bridge-splitting of trans-[PtCl2(η2-CH2CH2)]2 by weak nucleophiles: Crystal and molecular structure of trans-[PtCl2(η2-CH2CH2)(MeCN)

Bridge-splitting of trans-[PtCl2(eta(2)-CH2=CH2)](2), 1, by L in dichloromethane yields trans-[PtCl2(eta(2)-CH2=CH2)(L)] (L = THF, 2, or MeCN, 3) with bridge-splitting equilibrium constants of 0.0289 +/- 0.0007 and 3601 +/- 215 mol(-1) dm(3), respectively, as determined by UV/Vis measurements. The reaction of 3 in MeCN with Cl- is essentially quantitative. The crystal structure of trans-[PtCl2(eta(2)-CH2=CH2)(CH3CN)] is reported. (C) 2009 Elsevier B.V. All rights reserved.

Unexpected formation of dihaloplatinum(II) and platinum(IV) complexes in the reaction of [PtMe2(bu2bpy)] with 1,2-dibromotetrachloroethane: Crystal structure of trans-[PtMe2BrCl(bu2bpy)

The platinum(II) complex [PtMe2(bu2bpy)] (bu2bpy = 4,4′-di-tert-butyl-2,2′-bipyridine) (1) reacted with 1,2-dibromotetrachloroethane in a 2:1 mole ratio of Pt(II): (CBrCl2)2 to afford trans-[PtMe2BrCl(bu2bpy)] (2) and [PtCl2(bu2bpy)] (3). The 1H NMR spectroscopy shows that the Pt–Me bond cleavage is mainly involved after a fast oxidative addition reaction. Complex trans-[PtMe2BrCl(bu2bpy)] (2) has been characterized by X-ray diffraction which shows that platinum adopts an octahedral geometry.

Molecular and crystal structure of trans and cis isomers of 3-cyano-4-[2-(4-methoxyphenyl)vinyl]-6,6-dimethyl-5,6-dihydro-2H-pyran

Monocrystals of the trans and cis isomers of 3-cyano-4-[2-(4-methoxyphenyl)vinyl]-6,6-dimethyl-5,6-dihydro-2H-pyran have been obtained and an X-ray structural analysis of them has been carried out. Both compounds have a molecular structure corresponding to symmetry group C 1 . The heterocyclic ring is in a distorted envelope conformation. The crystals of the trans isomer are rhombic and have a fir-tree type of packing. The crystal packing of the cis isomer is formed by pairs of molecules, each of which consists of only one enantiomer.

Butenynyl and Vinylidene Complexes of Ruthenium

Reaction of ruthenium bis-acetylide complexes with 2,6-lutidinium tetrafluoroborate gave butenynyl complexes cis-[Ru(η3-RC≡CC═C(H)R)(PMe3)4]BF4 in moderate to good yields. The structure of cis-[Ru(η3-tBuC≡CC═C(H)tBu)(PMe3)4]BF4 was determined crystallographically. Attempts to prepare cis-[Ru(η3-MeC≡CC═C(H)Me)(PMe3)4]BF4 resulted in the formation of two isomers, which differ in the stereochemistry about the double bond. The reaction of two bis-acetylide complexes with methyl triflate afforded butenynyl-type complexes cis-[Ru(η3-RC≡CC═C(Me)R)(PMe3)4]+ (R = Me, Ph). The mixed acetylide−vinylidene complex trans-[Ru(C≡CSiMe3)(C═CH2)(PMe3)4]PF6 was prepared by the reaction of trans-Ru(C≡CSiMe3)2(PMe3)4 with ammonium hexafluorophosphate. In addition, the crystal structure of trans-[Ru(C≡CH)(C═CH2)(PMe3)4]BF4 is reported.

Competing C−F Activation Pathways in the Reaction of Pt(0) with Fluoropyridines: Phosphine-Assistance versus Oxidative Addition

A survey of computed mechanisms for C-F bond activation at the 4-position of pentafluoropyridine by the model zero-valent bis-phosphine complex, [Pt(PH3)(PH2Me)], reveals three quite distinct pathways leading to square-planar Pt(II) products. Direct oxidative addition leads to cis-[Pt(F)(4-C5NF4)(PH3)(PH2Me)] via a conventional 3-center transition state. This process competes with two different phosphine-assisted mechanisms in which C-F activation involves fluorine transfer to a phosphorus center via novel 4-center transition states. The more accessible of the two phosphine-assisted processes involves concerted transfer of an alkyl group from phosphorus to the metal to give a platinum(alkyl)(fluorophosphine), trans-[Pt(Me)(4-C5NF4)(PH3)(PH2F)], analogues of which have been observed experimentally. The second phosphine-assisted pathway sees fluorine transfer to one of the phosphine ligands with formation of a metastable metallophosphorane intermediate from which either alkyl or fluorine transfer to the metal is possible. Both Pt-fluoride and Pt(alkyl)(fluorophosphine) products are therefore accessible via this route. Our calculations highlight the central role of metallophosphorane species, either as intermediates or transition states, in aromatic C-F bond activation. In addition, the similar computed barriers for all three processes suggest that Pt-fluoride species should be accessible. This is confirmed experimentally by the reaction of [Pt(PR3)2] species (R = isopropyl (iPr), cyclohexyl (Cy), and cyclopentyl (Cyp)) with 2,3,5-trifluoro-4-(trifluoromethyl)pyridine to give cis-[Pt(F){2-C5NHF2(CF3)}(PR3)2]. These species subsequently convert to the trans-isomers, either thermally or photochemically. The crystal structure of cis-[Pt(F){2-C5NHF2(CF3)}(P iPr3)2] shows planar coordination at Pt with r(F-Pt) = 2.029(3) A and P(1)-Pt-P(2) = 109.10(3) degrees. The crystal structure of trans-[Pt(F){2-C5NHF2(CF3)}(PCyp3)2] shows standard square-planar coordination at Pt with r(F-Pt) = 2.040(19) A.

Dinitrogen and Acetylide Complexes of Low-Valent Chromium

Reaction of trans-(dmpe) 2CrCl2 (dmpe=1,2-bis(dimethylphosphino)ethane) with one equivalent of LiCCSiMe3 and one equivalent of nBuLi in THF under a dinitrogen atmosphere affords dark orange trans,trans-[(Me 3SiCC)(dmpe)2Cr]2(micro-N2).hexane (1). Under similar conditions but in the absence of acteylide ligand, the reaction of trans-(dmpe)2CrCl2 with 2 equivalents of nBuLi yields the previously characterized complex trans-(dmpe)2Cr(N2)2 (2), while the reaction of trans-(dmpe)2CrCl2 with 2 equivalents of LiCCSiMe3 in THF yields trans-(dmpe)2Cr(CCSiMe3)2 (3). Compound 3 can also be synthesized by irradiating a mixture of trans-(dmpe)2CrMe2 and HCCSiMe3 or by reduction of HCCSiMe3 with compound 2. The magnetic properties, electrochemistry, and crystal structure of trans,trans-[(Me3SiCC)(dmpe)2Cr]2(micro-N2) are consistent with the complex containing two CrI ions bridged by a neutral N2 moiety, with a 1.178(10) A N[TRIPLE BOND]N bond distance. For complex 1 redox processes centered at E1/2=-1.69 V (DeltaEp=185 mV) and -1.43 V (DeltaEp=182 mV) versus Fe(Cp)2/Fe(Cp)2+ are assigned to the CrICrI/CrICrII and CrICrII/CrIICrII couples, respectively. For trans-(dmpe)2Cr(CCSiMe3)2 a reversible couple assigned as the CrII/III couple was observed at -1.59 V (DeltaEp=242 mV) versus Fe(Cp)2/Fe(Cp)2+. The dinuclear CrI-dinitrogen complex 1 has a room temperature magnetic moment of 2.77 microB while compound 3 displays a moment of 2.55 microB. Density-functional theory calculations performed on a model compound of 1, namely, trans,trans-[(HCC)(dpe)2Cr]2(micro-N2) (dpe=diphospinoethane), indicate that oxidation of the molecule should result in weakening of the dinitrogen triple bond.

Solvent induced oxidative addition and phenyl migration in trans-[RhCl(CO)(SbPh 3) 3]: Crystal structure of trans- mer-[Rh(Cl) 2(Ph)(SbPh 3) 3

Phenyl migration and oxidative addition were observed in nitromethane containing solutions of trans-[RhCl(CO)(SbPh 3) n ] ( n = 2 or 3) and free SbPh 3. A Rh(III) product resulting from phenyl migration and oxidative addition to Rh(I), trans- mer-[Rh(Cl) 2(Ph)(SbPh 3) 3], was characterised by X-ray crystallography.

Co(III) complexes of Me-salpn and Me-salbn and the ring size effect on the coordination modes and electrochemical properties: The crystal structures of trans-[Co III(Me-salpn)(py) 2]PF 6 and cis- α-[Co III(Me-salbn)(4-Mepy) 2]BPh 4 · 4-Mepy

The synthesis and characterization of a series of cobalt(III) complexes of the general type [Co(N 2O 2)(L 2)] + are described. The N 2O 2 Schiff base ligands used are Me-salpn (H 2Me-salpn = N, N′-bis(methylsalicylidene)-1,3-propylenediamine) ( 1– 3) and Me-salbn (H 2Me-salbn = N, N′-bis(methylsalicylidene)-1,4-butylenediamine) ( 4– 5). The two ancillary ligands L include: pyridine (py) 1, 3-metheylpyridine (3-Mepy) 2, 1-methylimidazole (1-MeIm) 3, 4-methylpyridine (4-Mepy) 4 and pyridine (py) 5. These complexes have been characterized by elemental analyses, IR, UV–Vis, and 1H NMR spectroscopy. The crystal structures of trans-[Co III(Me-salpn)(py) 2]PF 6, 1, and cis- α-[Co III(Me-salbn)(4-Mepy) 2]BPh 4 · 4-Mepy, 4, have been determined by X-ray diffraction. Examination of the solution and crystalline structures revealed that the outer coordination sphere of the complexes exerts a noticeable influence on the inner coordination sphere of the Co(III) ion. The electrochemical reduction of these complexes at a glassy carbon electrode in acetonitrile solution indicates that the first reduction process corresponding to Co III–Co II is electrochemically irreversible, which is accompanied by the dissociation of the axial (R-py)–cobalt bonds. It has also been observed that the Co(III) state is stabilized with increasing the flexibility of the ligand environment.

Phosphanimin‐Derivate des Osmium(IV): Kristallstrukturen von trans‐[OsCl4(HNPEt3)2] und (H2NPPh3)2[OsCl6]·2CH3CN

AbstractPhosphoraneimine Derivatives of Osmium(IV): Crystal Structures of trans‐[OsCl4(HNPEt3)2] and (H2NPPh3)2[OsCl6]·2CH3CNtrans‐[OsCl4(HNPEt3)2] (1) was prepared by reaction of osmium pentachloride with the silylated phosphoraneimine Me3SiNPEt3 in dichloromethane solution forming yellow moisture sensitive single crystals. The hexachloroosmate(IV) (H2NPPh3)2[OsCl6]·2CH3CN (2) was obtained as yellow single crystals from osmium pentachloride and N‐chlorotriphenylphosphoraneimine, ClNPPh3, in acetonitrile solution. 1 and 2 are characterized by IR spectroscopy and single crystal X‐ray structure determinations.1: Space group P21/c, Z = 2, lattice dimensions at 193 K: a = 830.9(1), b = 1031.1(1), c = 1307.7(1) pm, β = 106.15(1)°, R1 = 0.0248. 1 forms centrosymmetric molecules with distances Os–N of 202.9(4) pm and Os–Cl of 234.7 pm on average.2: Space group ${\rm P}{\bar 1}$, Z = 2, lattice dimensions at 193 K: a = 1030.7(1), b = 1432.6(1), c = 1448.8(1) pm, α = 90.98(1)°, β = 92.40(1)°, γ = 92.98(1)°, R1= 0.0545. 2 forms an ionic structure with (H2NPPh3)+ cations and two different site positions of the centrosymmetric [OsCl6]2− anions. The cations are connected with one of the anions by N‐H···Cl bridges as well as with the solvate molecules CH3CN by N–H···N bridges.

Synthesis and characterization of platinum – selenium derivatives: X-ray structure of trans-Pt(PEt3)2(SePh)2

The crystal structure of trans-[((bis)triethylphosphine)(bis(phenylselenato))platinum (II)] has been determined by single crystal X-ray diffraction. Crystallization occurs in the triclinic space group P-1 (No. 2) with a = 8.9964(2) A, b = 11.5103(2) A, c = 14.9335(3) A; α = 85.8750(10)°, β = 72.5350(10)°, γ = 68.4450(10)°. Details of the structure and spectroscopic results are presented and discussed and comparisons are made with related square planar platinum (II) structures.

Thio- and seleno-ether complexes with Group 4 tetrahalides and tin tetrachloride: preparation and use in CVD for metal chalcogenide films

Reaction of TiCl(4) or ZrI(4) with the soft, neutral o-C(6)H(4)(CH(2)EMe)(2) (E = S or Se) in anhydrous CH(2)Cl(2) (or toluene) yields the distorted octahedral chelate complexes [MX(4){o-C(6)H(4)(CH(2)EMe)(2)}]. Using Et(2)Se gives [MX(4)(Et(2)Se)(2)] (M = Zr, X = Cl or I; M = Hf, X = I). The Sn(IV) analogues, [SnCl(4){o-C(6)H(4)(CH(2)EMe)(2)}] and [SnCl(4)(Et(2)Se)(2)] were obtained similarly. These complexes have been characterised spectroscopically and analytically, and crystal structures of trans-[SnCl(4)(Et(2)Se)(2)] and some selenonium salts derived as minor by-products from the parent Group 4 complexes are described. The neutral chalcogenoether complexes have been evaluated as single source precursors to ME(2)/ME thin films via LPCVD. [TiCl(4){o-C(6)H(4)(CH(2)EMe)(2)}] leads to the deposition of air and moisture stable TiE(2) films (with no residual Cl). Coverage of the substrate is uniform with platelet growth perpendicular to the surface. The heavier Zr(IV) species do not lead to significant ZrE(2) deposition. On the other hand, LPCVD of [SnCl(4){o-C(6)H(4)(CH(2)SMe)(2)}] leads to deposition of SnS(2) at lower temperatures and SnS at higher temperatures, while [SnCl(4){o-C(6)H(4)(CH(2)SeMe)(2)}] gives rather uneven coatings of SnSe(2). The Et(2)Se derivative, [SnCl(4)(Et(2)Se)(2)] leads to uniform deposition of SnSe(2) with growth perpendicular to the substrate surface. The SnE(2)/SnE films are stable indefinitely to air and moisture. The generation of TiS(2), SnS(2) and SnS in this way are very rare examples of metal sulfide deposition from C-S bond fission within a thioether complex.

Preparation and characterization of mixed-ligand cobalt(iii) complexes containing (3-aminopropyl)dimethylphosphine (pdmp). Conformation of the six-membered pdmp chelate ring

Several new cobalt(III) complexes containing (3-aminopropyl)dimethylphosphine (pdmp) have been prepared, and their molecular structures have been determined. A dichloro complex of trans(Cl,Cl)-cis(P,P)-[CoCl(2)(pdmp)(2)]PF(6) (1) was prepared from trans-[CoCl(2)(py)(4)]Cl.6H(2)O and pdmp. X-Ray crystallography confirmed the (C(2))-chair(2) conformation of two six-membered pdmp chelate rings in 1, while the analogous 1,3-bis(dimethylphosphino)propane (dmpp) complex trans-[CoCl(2)(dmpp)(2)]ClO(4) (3) exhibited the (D(2d))-twist(2) conformation. Substitution reactions of 1 for ethane-1,2-diamine (en), pentane-2,4-dionate (acac), and N,N-dimethyldithiocarbamate (dtc) gave the mixed-ligand tris(chelate)-type complexes of [Co(en)(2)(pdmp)]Cl(2)(PF(6)) (5), [Co(acac)(pdmp)(2)](PF(6))(2) (7), and [Co(dtc)(3-n)(pdmp)(n)](PF(6))(n) [n = 1 (9) or 2 (10)], respectively. The conformer of the complex cation in 5 was assigned as lel.ob.chair by X-ray analysis. In the case of the acac complex 7, both trans(P,N) (7a) and trans(N,N) (7b) isomers were isolated, and the complex cations were characterized as syn-chair(2) and anti-chair(2) conformers, respectively, with respect to the six-membered pdmp chelate rings. These conformers coincide with the most stable ones anticipated by the DFT optimum geometry calculations. In the crystal structure of trans(P,N)-[Co(dtc)(pdmp)(2)](BPh(4))(2) (10') one of the pdmp chelate rings adopted a skew-boat (twist) conformation, which reduced the intramolecular steric ring-ring interaction effectively. The DFT optimized geometries for several isomers and/or conformers of [CoCl(2)(pdmp)(2)](+) were compared.

Tin(IV) Fluoride Complexes with Tertiary Phosphane Ligands – A Comparison of Hard and Soft Donor Ligands

AbstractThe first phosphane complexes of the hard Lewis acid SnF4 have been synthesised including trans‐[SnF4(PR3)2] (R = Me or Cy) and cis‐[SnF4(diphosphane)] [diphosphane = R2P(CH2)2PR2, R = Me, Et, Ph or Cy; o‐C6H4(PR2)2, R = Me or Ph] and characterised by IR and multinuclear NMR (1H, 19F, 31P, 119Sn) spectroscopy. The crystal structures of trans‐[SnF4(PCy3)2] and cis‐[SnF4{Et2P(CH2)2PEt2}] are reported. Tin(IV) fluoride complexes of 2,2′‐bipyridyl, 1,10‐phenanthroline, MeO(CH2)2OMe, Me2N(CH2)2NMe2, pyridine and THF have been characterised by multinuclear NMR spectroscopy, the structures of cis‐[SnF4(L–L)] (L–L = 1,10‐phenanthroline and MeO(CH2)2OMe) determined, and the properties were compared with those of the phosphane complexes. Complexes of o‐C6H4(PMe2)2, Et2P(CH2)2PEt2, and MeC(CH2AsMe2)3 with SnCl4 and SnBr4 are also reported and the structures of cis‐[SnCl4{Et2P(CH2)2PEt2}] and cis‐[SnBr4{κ2‐MeC(CH2AsMe2)3}] described. Attempts to prepare tertiary arsane complexes of SnF4 have been unsuccessful. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Formation of Coordinated C-Nitroso Compounds by Reaction of K[IrCl5NO] with Alkenes

Coordinated C-nitrosochloroalkanes were obtained by electrophilic addition of K[IrCl5NO] to cyclooctene or dicyclopentadiene; in the last case, the crystal structure of trans-[IrCl4(CH3CN)(syn-1-chloro-2-nitroso-1,2-dihydrodicyclopentadiene)] was determined by X-ray diffraction. Although the reaction between NOCl and alkenes is well-known, there are very few examples of clean electrophilic addition of coordinated NO+ to alkenes.