Chloro(η6‐p‐cymene)(phosphoramidite)ruthenium(II), a 16‐Electron Fragment Stabilized by an η2‐Aryl–Metal Interaction,and Its Use in Asymmetric Cyclopropanation

Chloride abstraction from the half‐sandwich complexes [RuCl₂(η⁶‐p‐cymene)(P*‐κP)] ( 2a : P* = (S_a,R,R)‐ 1a = (1S_a)‐[1,1′‐binaphthalene]‐2,2′‐diyl bis[(1R)‐1‐phenylethyl)]phosphoramidite; 2b : P* = (S_a,R,R)‐ 1b = (1S_a)‐[1,1′‐binaphthalene]‐2,2′‐diyl bis[(1R)‐(1‐(1‐naphthalen‐1‐yl)ethyl]phosphoramidite) with (Et₃O)[PF₆] or Tl[PF₆] gives the cationic, 18‐electron complexes dichloro(η⁶‐p‐cymene){(1S_a)‐[1,1′‐binaphthalene]‐2,2′‐diyl {(1R)‐1‐[(1,2‐η)‐phenyl]ethyl}[(1R)‐1‐phenylethyl]phosphoramidite‐κP}ruthenium(II) hexafluorophosphate ( 3a ) and [Ru(S)]‐dichloro(η⁶‐p‐cymene){(1S_a)‐[1,1′‐binaphthalene]‐2,2′‐diyl {(1R)‐1‐[(1,2‐η)‐naphthalen‐1‐yl]ethyl}[(1R)‐1‐(naphthalen‐1‐yl)ethyl]phosphoramidite‐κP)ruthenium(II) hexafluorophosphate ( 3b ), which feature the η²‐coordination of one aryl substituent of the phosphoramidite ligand, as indicated by ¹H‐, ¹³C‐, and ³¹P‐NMR spectroscopy and confirmed by an X‐ray study of 3b . Additionally, the dissociation of p‐cymene from 2a and 3a gives dichloro{(1S_a)‐[1,1′‐binaphthalene]‐2,2′‐diyl [(1R)‐(1‐(η⁶‐phenyl)ethyl][(1R)‐1‐phenylethyl]phosphoramidite‐κP)ruthenium(II) ( 4a ) and di‐μ‐chlorobis{(1S_a)‐[1,1′‐binaphthalene]‐2,2′‐diyl [(1R)‐1‐(η⁶‐phenyl)ethyl][(1R)‐1‐phenylethyl]phosphoramidite‐κP}diruthenium(II) bis(hexafluorophosphate) ( 5a ), respectively, in which one phenyl group of the N‐substituents is η⁶‐coordinated to the Ru‐center. Complexes 3a and 3b catalyze the asymmetric cyclopropanation of α‐methylstyrene with ethyl diazoacetate with up to 86 and 87% ee for the cis‐ and the trans‐isomers, respectively.     

Organotin–Oxido Cluster‐Based Multiferrocenyl Complexes Obtained by Hydrolysis of Ferrocenyl‐Functionalized Organotin Chlorides

Three organotin–oxido clusters were formed by hydrolysis of ferrocenyl‐functionalized organotin chloride precursors in the presence of NaEPh (E=S, Se). [R^FcSnCl₃?HCl] ( C ; R^Fc = CMe₂CH₂C(Me)?N?N?C(Me)Fc) and [SnCl₆]^2? formed {(R^FcSnCl₂)₃[Sn(OH)₆]}[SnCl₃] ( 3 a ) and {(R^FcSnCl₂)₃[Sn(OH)₆]}[PhSeO₃] ( 3 b ), bearing an unprecedented [Sn₄O₆] unit, in a one‐pot synthesis or stepwise through [(R^FcSnCl₂)₂Se] ( 1 ) plus [(R^FcSnCl₂)SePh] ( 2 ). A one‐pot reaction starting out from FcSnCl₃ gave [(FcSn)₉(OH)₆O₈Cl₅] ( 4 ), which represents the largest Fc‐decorated Sn/O cluster reported to date.     

Reaction of the Pincer‐type Ligand {2, 6‐[P(O)(OEt)2]2‐4‐tert‐Bu‐C6H2}— with [Ph3C]+[PF6]—. Unprecedented Rearrangement and Carbon‐Carbon Bond Formation

The reaction of the organolithium derivative {2, 6‐[P(O)(OEt)₂]₂‐4‐tert‐Bu‐C₆H₂}Li ( 1 ‐Li) with [Ph₃C]⁺[PF₆]^— gave the substituted biphenyl derivative 4‐[(C₆H₅)₂CH]‐4′‐[tert‐Bu]‐2′, 6′‐[P(O)(OEt)₂]₂‐1, 1′‐biphenyl ( 5 ) which was characterized by ¹H, ¹³C and ³¹P NMR spectroscopy and single crystal X‐ray analysis. Ab initio MO‐calculations reveal the intramolecular O···C distances in 5 of 2.952(4) and 2.988(5)Å being shorter than the sum of the van der Waals radii of oxygen and carbon to be the result of crystal packing effects. Also reported are the synthesis and structure of the bromine‐substituted derivative {2, 6‐[P(O)(OEt)₂]₂‐4‐tert‐Bu]C₆H₂}Br ( 9 ) and the structure of the protonated ligand 5‐tert‐Bu‐1, 3‐[P(O)(OEt)₂]₂C₆H₃ ( 1 ‐H). The structures of 1 ‐H, 5 , and 9 are compared with those of related metal‐substituted derivatives.     

Diimido‐, Imido(oxo)‐, Dioxo‐ und Imido(alkyliden)‐Halbsandwich‐Verbindungen über selektive Hydrolyse und α—H‐Abstraktion an Organylkomplexen des sechswertigen Molybdäns und Wolframs

Diimido, Imido Oxo, Dioxo, and Imido Alkylidene Halfsandwich Compounds via Selective Hydrolysis and α—H Abstraction in Molybdenum(VI) and Tungsten(VI) Organyl Complexes Organometal imides [(η⁵‐C₅R₅)M(NR′)₂Ph] (M = Mo, W, R = H, Me, R′ = Mes, tBu) 4 — 8 can be prepared by reaction of halfsandwich complexes [(η⁵‐C₅R₅)M(NR′)₂Cl] with phenyl lithium in good yields. Starting from phenyl complexes 4 — 8 as well as from previously described methyl compounds [(η⁵‐C₅Me₅)M(NtBu)₂Me] (M = Mo, W), reactions with aqueous HCl lead to imido(oxo) methyl and phenyl complexes [(η⁵‐C₅Me₅)M(NtBu)(O)(R)] M = Mo, R = Me ( 9 ), Ph ( 10 ); M = W, R = Ph ( 11 ) and dioxo complexes [(η⁵‐C₅Me₅)M(O)₂(CH₃)] M = Mo ( 12 ), M = W ( 13 ). Hydrolysis of organometal imides with conservation of M‐C σ and π bonds is in fact an attractive synthetic alternative for the synthesis of organometal oxides with respect to known strategies based on the oxidative decarbonylation of low valent alkyl CO and NO complexes. In a similar manner, protolysis of [(η⁵‐C₅H₅)W(NtBu)₂(CH₃)] and [(η⁵‐C₅Me₅)Mo(NtBu)₂(CH₃)] by HCl gas leads to [(η⁵‐C₅H₅)W(NtBu)Cl₂(CH₃)] 14 und [(η⁵‐C₅Me₅)Mo(NtBu)Cl₂(CH₃)] 15 with conservation of the M‐C bonds. The inert character of the relatively non‐polar M‐C σ bonds with respect to protolysis offers a strategy for the synthesis of methyl chloro complexes not accessible by partial methylation of [(η⁵‐C₅R₅)M(NR′)Cl₃] with MeLi. As pure substances only trimethyl compounds [(η⁵‐C₅R₅)M(NtBu)(CH₃)₃] 16 ‐ 18 , M = Mo, W, R = H, Me, are isolated. Imido(benzylidene) complexes [(η⁵‐C₅Me₅)M(NtBu)(CHPh)(CH₂Ph)] M = Mo ( 19 ), W ( 20 ) are generated by alkylation of [(η⁵‐C₅Me₅)M(NtBu)Cl₃] with PhCH₂MgCl via α‐H abstraction. Based on nmr data a trend of decreasing donor capability of the ligands [NtBu]^2— > [O]^2— > [CHR]^2— ? 2 [CH₃]^— > 2 [Cl]^— emerges.     

Activation of SO2 with [(η5‐C5Me5)2Ln(THF)2] (Ln=Eu,Yb) Leading to Dithionite and Sulfinate Complexes

The reaction of decamethylytterbocene [(η⁵‐C₅Me₅)₂Yb(THF)₂] with SO₂ at low temperature gave two new compounds, namely, the Yb^III dithionite/sulfinate complex [{(η⁵‐C₅Me₅)₂Yb(μ₃,1κ²O^1,3,2κ³O^2,2′,4‐S₂O₄)}₂{(η⁵‐C₅Me₅)Yb(μ,1κO,2κO′‐C₅Me₅SO₂)}₂] ( 1 ) and the Yb^III dithionite complex [{(η⁵‐C₅Me₅)₂Yb}₂(μ,1κ²O^1,3,2κ²O^2,4‐S₂O₄)] ( 2 ). After extraction of 1 , the mixture was heated to give the dinuclear tetrasulfinate complex [{(η⁵‐C₅Me₅)Yb}₂(μ,κO,κO’‐C₅Me₅SO₂)₄] ( 3 a ). In contrast, from the reaction of [(η⁵‐C₅Me₅)₂Eu(THF)₂] with SO₂ only the tetrasulfinate complex [{(η⁵‐C₅Me₅)Eu}₂(μ,κO,κO’‐C₅Me₅SO₂)₄] ( 3 b ) was isolated. Two major reaction pathways were observed: 1) reductive coupling of two SO₂ molecules to form the dithionite anion S₂O₄^2?; and 2) nucleophilic attack of one metallocene C₅Me₅ ligand on the sulfur atom of SO₂. The compounds presented are the first dithionite and sulfinate complexes of the f‐elements.     

[μ‐1κ2O,O′:2(η5)‐Cyclopentadienylcarboxylato][2(η5)‐diphenylphosphinocyclopentadienyl]bis[1,1(η5)‐tetramethylcyclopentadienyl]iron(II)titanium(III)

Reacting stoichiometric amounts of 1‐(diphenylphosphino)ferrocene­carboxylic acid and [Ti(η⁵‐C₅HMe₄)₂(η²‐Me₃SiC[triple‐bond]CSiMe₃)] produced the title carboxyl­atotitanocene complex, [{μ‐1κ²O,O′:2(η⁵)‐C₅H₄CO₂}{2(η⁵)‐C₅H₄P(C₆H₅)₂}{1(η⁵)‐C₅H(CH₃)₄}₂Fe^IITi^III] or [FeTi(C₉H₁₃)₂(C₆H₄O₂)(C₁₇H₁₄P)]. The angle subtended by the Ti/O/O′ plane, where O and O′ are the donor atoms of the κ²‐carboxy­late group, and the plane of the carboxyl‐substituted ferrocene cyclo­penta­dienyl is 24.93 (6)°.     

Synthese,Struktur und Reaktivität von η3‐1,2‐Diphosphaallylkomplexen sowie von [{(η5‐C5H5)(CO)2W–Co(CO)3}{μ‐AsCH(SiMe3)2}(μ‐CO)]

Syntheses, Structure and Reactivity of η³‐1,2‐Diphosphaallyl Complexes and [{(η⁵‐C₅H₅)(CO)₂W–Co(CO)₃}{μ‐AsCH(SiMe₃)₂}(μ‐CO)] Reaction of ClP=C(SiMe₂iPr)₂ ( 3 ) with Na[Mo(CO)₃(η⁵‐C₅H₅)] afforded the phosphavinylidene complex [(η⁵‐C₅H₅)(CO)₂Mo=P=C(SiMe₂iPr)₂] ( 4 ) which in situ was converted into the η¹‐1,2‐diphosphaallyl complex [η⁵‐(C₅H₅)(CO)₂Mo{η³‐tBuPPC(SiMe₂iPr)₂] ( 6 ) by treatment with the phosphaalkene tBuP=C(NMe₂)₂. The chloroarsanyl complexes [(η⁵‐C₅H₅)(CO)₃M–As(Cl)CH(SiMe₃)₂] [where M = Mo ( 9 ); M = W ( 10 )] resulted from the reaction of Na[M(CO)₃(η⁵‐C₅H₅)] (M = Mo, W) with Cl₂AsCH(SiMe₃)₂. The tungsten derivative 10 and Na[Co(CO)₄] underwent reaction to give the dinuclear μ‐arsinidene complex [(η⁵‐C₅H₅)(CO)₂W–Co(CO)₃{μ‐AsCH(SiMe₃)₂}(μ‐CO)] ( 11 ). Treatment of [(η⁵‐C₅H₅)(CO)₂Mo{η³‐tBuPPC(SiMe₃)₂}] ( 1 ) with an equimolar amount of ethereal HBF₄ gave rise to a 85/15 mixture of the saline complexes [(η⁵‐C₅H₅)(CO)₂Mo{η²‐tBu(H)P–P(F)CH(SiMe₃)₂}]BF₄ ( 18 ) and [Cp(CO)₂Mo{F₂PCH(SiMe₃)₂}(tBuPH₂)]BF₄ ( 19 ) by HF‐addition to the PC bond of the η³‐diphosphaallyl ligand and subsequent protonation ( 18 ) and/or scission of the PP bond by the acid ( 19 ). Consistently 19 was the sole product when 1 was allowed to react with an excess of ethereal HBF₄. The products 6 , 9 , 10 , 11 , 18 and 19 were characterized by means of spectroscopy (IR, ¹H‐, ¹³C{¹H}‐, ³¹P{¹H}‐NMR, MS). Moreover, the molecular structures of 6 , 11 and 18 were determined by X‐ray diffraction analysis.     

The Complexed 1,3‐Diphospha‐2‐Arsaallyl Radical and Its Cationic and Anionic Derivatives

Photolysis of [Cp*As{W(CO)₅}₂] ( 1 a ) in the presence of Mes*P?PMes* (Mes*=2,4,6‐tri‐tert‐butylphenyl) leads to the novel 1,3‐diphospha‐2‐arsaallyl radical [(CO)₅W(μ,η²:η¹‐P₂AsMes*₂)W(CO)₄] ( 2 a ). The frontier orbitals of the radical 2 a are indicative of a stable π‐allylic system that is only marginally influenced by the d orbitals of the two tungsten atoms. The SOMO and the corresponding spin density distribution of the radical 2 a show that the unpaired electron is preferentially located at the two equivalent terminal phosphorus atoms, which has been confirmed by EPR spectroscopy. The protonated derivative of 2 a , the complex [(CO)₅W(μ,η²:η¹‐P₂As(H)Mes*₂)W(CO)₄] ( 6 a ) is formed during chromatographic workup, whereas the additional products [Mes*P?PMes*{W(CO)₅}] as the Z‐isomer ( 3 ) and the E‐isomer ( 4 ), and [As₂{W(CO)₅}₃] ( 5 ) are produced as a result of a decomposition reaction of radical 2 a . Reduction of radical 2 a yields the stable anion [(CO)₅W(μ,η²:η¹‐P₂AsMes*₂)W(CO)₄]^? in 7 a , whereas upon oxidation the corresponding cationic complex [(CO)₅W(μ,η²:η¹‐P₂AsMes*₂)W(CO)₄][SbF₆] ( 8 a ) is formed, which is only stable at low temperatures in solution. Compounds 2 a , 7 a , and 8 a represent the hitherto elusive complexed redox congeners of the diphospha‐arsa‐allyl system. The analogous oxidation of the triphosphaallyl radical [(CO)₅W(μ,η²:η¹‐ P₃Mes*₂)W(CO)₄] ( 2 b ) also leads to an allyl cation, which decomposes under CH activation to the phosphine derivative [(CO)₅W{μ,η²:η¹‐P₃(Mes*)(C₅H₂tBu₂C(CH₃)₂CH₂)}W(CO)₄] ( 9 ), in which a CH bond of a methyl group of the Mes* substituent has been activated. All new products have been characterized by NMR spectrometry and IR spectroscopy, and compounds 2 a , 3 , 6 a , 7 a , and 9 by X‐ray diffraction analysis.     

Quinine‐Derived Imidazolidin‐2‐imine Ligands: Synthesis,Coordination Chemistry,and Application in Catalytic Transfer Hydrogenation

Two new optically active bidentate N,N‐ligands, DMIQCI ( 3a ) and DMIQCD ( 3b ), containing a quinuclidine core and an imidazolidin‐2‐imine unit, were synthesized. The reaction of these ligands with [(η⁵‐C₅Me₅)RuCl]₄ afforded the brick‐red ruthenium(II) complexes [(η⁵‐C₅Me₅)Ru(DMIQCI)Cl] ( 4 ) and [(η⁵‐C₅Me₅)Ru(DMIQCD)Cl] ( 5 ), which were used as catalysts in the transfer hydrogenation of acetophenone in boiling 2‐propanol. The reactions of 3a and 3b with [(COD)PdCl₂] (COD = 1,5‐cycloocta‐diene) and with [(DME)NiBr₂] (DME = 1,2‐dimethoxyethane) afforded the square‐planar palladium(II) complexes [(DMIQCI)PdCl₂] ( 7 ) and [(DMIQCD)PdCl₂] ( 8 ) or the tetrahedral nickel(II) complexes [(DMIQCI)NiBr₂] ( 9 ) and [(DMIQCD)NiBr₂] ( 10 ), respectively. The X‐ray crystal structures of 4 , 7 , 9· THF, and 10 are reported.     

Synthese und Kristallstruktur des heterobimetallischen Diorganozinndichlorids (FcN,N)2SnCl2 (FcN,N—: (η5‐C5H5)Fe{(η5‐C5H3[CH(CH3)N(CH3)CH2CH2NMe2]‐2}—)

Synthesis and Crystal Structure of the Heterobimetallic Diorganotindichloride (FcN, N)₂SnCl₂ (FcN, N^—: (η⁵‐C₅H₅)Fe{η⁵‐C₅H₃[CH(CH₃)N(CH₃)CH₂CH₂NMe₂]‐2}^—) The heterobimetallic title compound [(FcN, N)₂SnCl₂] ( 1 ) was obtained by the reaction of [LiFcN, N] with SnCl₄ in the molar ratio 1:1 in diethylether as a solvent. The two FcN, N^— ligands in 1 are bound to Sn through a C‐Sn σ‐bond; the amino N atoms of the side‐chain in FcN, N^— remain uncoordinated. The crystals contain monomeric molecules with a pseudo‐tetrahedral coordination at the Sn atom: Space group P2₁/c; Z = 4, lattice dimensions at —90 °C: a = 9.6425(2), b = 21.7974(6), c = 18.4365(4) Å, β = 100.809(2)°, R1_obs· = 0.051, wR2_obs· = 0.136.     

Untersuchungen zur P–P‐Bindungsknüpfung in der Koordinationssphäre von Übergangsmetallen

Investigations of P–P Bond Formation Reactions in the Coordination Sphere of Transition Metals The reaction of [CpW(CO)₃]^– with PCl₃ leads to the transition metal substituted dichlorphosphines [{CpW(CO)₃}PCl₂] ( 1 ) and [{Cp(CO)₃W}PCl₂{WCl(CO)₂Cp}] ( 2 ). The X‐ray structure of 2 reveals the Lewis acid/base character of this compound. Reactions of 1 and [Cr(CO)₅Cp*PCl₂], respectively, with metalates of the type [M(CO)₃Cp′]^– (M′ = Mo, W; Cp′ = η⁵‐C₅H₄tBu) afford the cyclo‐P₃ complexes [(η³‐P₃)MCp′(CO)₃] ( 3 ) (M = W) and ( 4 ) (M = Mo) and the compounds [(μ,η²‐P₂{Cr(CO)₅}₂){Mo(CO)₂Cp}₂] ( 5 ) and [{μ₃‐PW(CO)₃Cp′}{W(CO)₂Cp′}₂] ( 6 ), respectively. Complex 6 possesses a planar homoleptic W₃P moiety revealing delocalised multiple bonds within the W₂P‐subunit. Reducing [(CO)₅WPCl₃] with magnesium leads to the formation of the phosphinidene complex [{(CO)₅W}₂PCl], whereas the reduction of [CpW(CO)₃PCl₂] ( 1 ) with magnesium yields the cyclo‐P₃ complex 3 together with P₄ phosphorus.     

Cobalt(II) Complexes with N‐Thioacylamidophosphates and 2,2′‐Bipyridyl and 1,10‐Phenathroline. Crystal Structures,Solution 1H NMR Spectral and Magnetic Properties

Structure and magnetic properties of N‐diisopropoxyphosphorylthiobenzamide PhC(S)‐N(H)‐P(O)(OiPr)₂ ( HL^I ) and N‐diisopropoxyphosphoryl‐N′‐phenylthiocarbamide PhN(H)‐C(S)‐N(H)‐P(O)(OiPr)₂ ( HL^II ) complexes with the Co^II cation of formulas [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂] ( 1 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂] ( 2 ), [Co{PhC(S)‐N(H)‐P(O)(OiPr)₂}₂{PhC(S)‐N‐P(O)(OiPr)₂}₂] ( 1a ) and [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂}(2,2′‐bipy)] ( 3 ), [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂(1,10‐phen)] ( 4 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂(2,2′‐bipy)] ( 5 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂(1,10‐phen)] ( 6 ) were investigated. Paramagnetic shifts in the ¹H NMR spectrum were observed for high‐spin Co^II complexes with HL^I,II , incorporating the S‐C‐N‐P‐O chelate moiety and two aromatic chelate ligands. Investigation of the thermal dependence of the magnetic susceptibility has shown that the extended materials 1‐2 and 6 show ferromagnetic exchange between distorted tetrahedral ( 1 , 2 ) or octahedral ( 1a , 6 ) metal atoms whereas 3 and 5 show antiferromagnetic properties. Compound 4 behaves as a spin‐canted ferromagnet, an antiferromagnetic ordering taking place below a critical temperature, T_c = 115 K. Complexes 1 and 1a were investigated by single crystal X‐ray diffraction. The cobalt(II) atom in complex 1 resides a distorted tetrahedral O₂S₂ environment formed by the C=S sulfur atoms and the P=O oxygen atoms of two deprotonated ligands. Complex 1a has a tetragonal‐bipyramidal structure, Co(O^ax)₂(O^eq)₂(S^eq)₂, and two neutral ligand molecules are coordinated in the axial positions through the oxygen atoms of the P=O groups. The base of the bipyramid is formed by two anionic ligands in the typical 1,5‐O,S coordination mode. The ligands are in a trans configuration.     

Exploring the Limits of Frustrated Lewis Pair Chemistry with Alkynes: Detection of a System that Favors 1,1‐Carboboration over Cooperative 1,2‐P/B‐Addition

The zirconocene complex [{(C₆F₅)₂B‐(CH₂)₃‐Cp}(Cp‐PtBu₂)ZrCl₂] ( 6 ; Cp=cyclo‐C₅H₄) was prepared by hydroboration of [(allyl‐Cp)(Cp‐PtBu₂)ZrCl₂] ( 5 ) with HB(C₆F₅)₂ (“Piers’ borane”). It represents a frustrated Lewis pair (FLP) in which both the Lewis acid and the Lewis base were attached at the metallocene framework. Its reaction with 1‐pentyne did not result in the 1,2‐addition of or deprotonation reaction by the FLP, but rather in the 1,1‐carboboration of the triple bond, thereby obtaining a Z/E mixture (1.2:1) of the respective organometallic substituted alkenes 7 . The analogous reaction of 1‐pentyne with the phosphorous‐free system [{(C₆F₅)₂B‐(CH₂)₃‐Cp)}CpZrCl₂] ( 9 ) gave the respective 1,1‐carboboration products ( Z‐10 / E‐10 ≈1.3:1).     

Syntheses and X‐Ray Crystal Structures of [Li(thf)4][SnCl5(thf)] and {[Li(Et2O)2]2‐(μ‐Cl2)2‐SnIVCl2}

The syntheses and single crystal X‐ray structure determinations are reported for [Li(thf)₄][SnCl₅(thf)] ( 1 ) and {[Li(Et₂O)₂]₂‐(μ‐Cl₂)₂‐Sn^IVCl₂} ( 2 ). Compound 1 is ionic with a tetrahedral coordinated lithium cation and distorted octahedral tin (IV) atom in the anion, while compound ( 2 ) is a centrosymmetric heteronuclear double salt of LiCl and SnCl₄. [Li(thf)₄][SnCl₅(thf)] is monoclinic, P2₁/n, a = 11.204(1), b = 15.599(1), c = 17.720(2) Å; β = 96.734(2)°, Z = 4, R 0.0418; {[Li(Et₂O)₂]₂‐(μ‐Cl₂)₂‐Sn^IVCl₂} is monoclinic, P2₁/n, a = 10.848(2), b = 12.764(2), c = 11.748(2) Å; β = 90.388(3)°, Z = 4, R = 0.0851.     

Substituted Ferrocenylboranes – Potential Ligand Precursors for ansa‐ Metallocenes,Constrained Geometry Complexes and ansa‐Diamido Complexes

A wide range of potential ligand precursors and related compounds have been synthesized from ferrocenyldibromoborane and ferrocenylenebis(dibromoborane) via salt elimination reactions. These comprise ligand precursors suitable for the preparation of (i) ansa‐metallocenes such as [FcB(η¹‐C₅H₅)₂] ( 2 ), [FcB(1‐C₉H₇)₂] ( 3 ), [FcB(3‐C₉H₇)₂] ( 4 ) and [1,1′‐fc{B(3‐C₉H₇)₂}₂] ( 11 ), (ii) constrained geometry complexes such as [FcB(1‐C₉H₇)N(H)Ph] ( 7 ) and [FcB(3‐C₉H₇)N(H)Ph] ( 8 ), (iii) ansa‐diamido complexes such as [FcB(N(H)Ph)₂] ( 9 ) as well as (iv) the related compounds [FcB(Br)N(H)tBu] ( 5 ), [FcB(Br)N(H)Ph] ( 6 ), [1,1′‐fc{B(Br)N(SiMe₃)₂}₂] ( 12 ) and [1,1′‐fc{B(Br)NiPr₂}₂] ( 13 ) (Fc = ferrocenyl, fc = ferrocenylene, C₅H₅ = cyclopentadienyl, C₉H₇ = indenyl). All new compounds have been characterised by multinuclear NMR spectroscopic techniques and in the case of 7 and 12 by X‐ray diffraction methods.     

[Fc2B2(Br)(μ‐NPEt3)2]+Br– – ein Ferrocenyl‐substituierter Phosphaniminato‐Komplex des Bors

[Fc₂B₂(Br)(μ‐NPEt₃)₂]⁺Br^– – a Ferrocenyl‐substituted Phosphoraneiminato Complex of Boron [Fc₂B₂(Br)(μ‐NPEt₃)₂]⁺Br^– has been prepared from ferrocenylboron dibromide, [Fe(η⁵‐C₅H₅)(η⁵‐C₅H₄BBr₂)], and the silylated phosphoraneimine Me₃SiNPEt₃ in dichloromethane solution to give orange‐red single crystals which were characterized by IR, NMR and ⁵⁷Fe Mössbauer spectra, as well as by a crystal structure determination. [Fc₂B₂(Br)(μ‐NPEt₃)₂]⁺Br^– · 3 CH₂Cl₂ ( 1 · 3 CH₂Cl₂): Space group P2₁/n, Z = 4, lattice dimensions at –50 °C: a = 1370.6(3), b = 2320.9(5), c = 1454.4(2), β = 95.38(1)°, R₁ = 0.061. In the cation of 1 the ferrocenyl‐substituted boron atoms are connected by the nitrogen atoms of the [NPEt₃]^– groups to form a planar B₂N₂ four‐membered ring. One of the boron atoms having planar, the other tetrahedral coordination.     

A one‐dimensional coordination polymer formed from the reaction of 1,1‐diphenyl‐3,3′‐[(1R,2R)‐cyclohexane‐1,2‐diylbis(azanediyl)]dibut‐2‐en‐1‐one with MnCl2·4H2O

In the title coordination polymer, catena‐poly[[dichloridomanganese(II)]‐μ‐1,1‐diphenyl‐3,3′‐[(1R,2R)‐cyclohexane‐1,2‐diylbis(azaniumylylidene)]dibut‐1‐en‐1‐olate‐κ²O:O′], [MnCl₂(C₂₆H₃₀N₂)]_n, synthesized by the reaction of the chiral Schiff base ligand 1,1‐diphenyl‐3,3′‐[(1R,2R)‐cyclohexane‐1,2‐diylbis(azanediyl)]dibut‐2‐en‐1‐one (L) with MnCl₂·4H₂O, the asymmetric unit contains one crystallographically unique Mn^II ion, one unique spacer ligand, L, and two chloride ions. Each Mn^II ion is four‐coordinated in a distorted tetrahedral coordination environment by two O atoms from two L ligands and by two chloride ligands. The Mn^II ions are bridged by L ligands to form a one‐dimensional chain structure along the a axis. The chloride ligands are monodentate (terminal). The ligand is in the zwitterionic enol form and displays intramolecular ionic N⁺—H...O⁻ hydrogen bonding and π–π interactions between pairs of phenyl rings which strengthen the chains.     

Bifunktionalisierte 1 H‐Phosphiren‐ und g1‐1‐Phosphaallen‐Wolframkomplexe

Bifunctionalized 1 H‐Phosphirene and g¹‐1‐Phosphaallene Tungsten Complexes The tungsten(0) complex [{(Me₃Si)₂HCPC(Ph)=N}W(CO)₅] 1 reacts upon heating with acetylene derivatives 2 a–d in toluene to form benzonitrile and the complexes [{(Me₃Si)₂HCPC(R)=COEt} · W(CO)₅] 5 a–d ( 5 a : R = SiMe₃; 5 b : R = SiPh₃; 5 c : R = SnMe₃; 5 d : R = SnPh₃) and [{(Me₃Si)₂HCP=C=C(OEt)R} · W(CO)₅] 6 a, b ( 6 a : R = SnMe₃; 6 b : R = SnPh₃), which have been isolated by chromatography; complexes 5 c and 6 a have been characterized as mixtures. Spectroscopic and mass spectrometric data are discussed. The crystal structure of the compound 5 a was determined by X‐ray single crystal structure analysis ( 5 a : space group P2₁/n, Z = 4, a = 977.6(2) pm, b = 1814.6(4) pm, c = 1628.0(4) pm, β = 93.95(2)°).     

Preparation and Structure of [(η5‐C5H5)Fe(CO){C(O)Ph}2]2Li2(2,2′‐Bipyridine): A Sequential Treatment of Nucleophile Followed by Lewis Base

Unable to elaborate (η⁵‐C₅H₅)Fe(CO)₂C(O)Ph by the nucleophile/electrophile sequences, the treatment of nucleophile PhLi followed by Lewis base 2,2′‐bipyridine instead leads to the meaningful isolation of [(η⁵‐C₅H₅)Fe(CO) {C(O)Ph}₂]₂Li₂(2,2′‐bipyridine).     

In‐ and Out‐of‐Cavity Interactions by Modulating the Size of Ruthenium Metallarectangles

Cationic (arene)ruthenium‐based tetranuclear complexes of the general formula [Ru₄(η⁶‐p‐cymene)₄(μ‐N∩N)₂(μ‐OO∩OO)₂]⁴⁺ were obtained from the dinuclear (arene)ruthenium complexes [Ru₂(η⁶‐p‐cymene)₂(μ‐OO∩OO)₂Cl₂] (p‐cymene=1‐methyl‐4‐(1‐methylethyl)benzene, OO∩OO=5,8‐dihydroxy‐1,4‐naphthoquinonato(2?), 9,10‐dihydroxy‐1,4‐anthraquinonato(2?), or 6,11‐dihydroxynaphthacene‐5,12‐dionato(2?)) by reaction with pyrazine or bipyridine linkers (N∩N=pyrazine, 4,4′‐bipyridine, 4,4′‐[(1E)‐ethene‐1,2‐diyl]bis[pyridine]) in the presence of silver trifluoromethanesulfonate (CF₃SO₃Ag) (Scheme). All complexes 4 – 12 were isolated in good yield as CF₃SO salts, and characterized by NMR and IR spectroscopy. The host–guest properties of the metallarectangles incorporating 4,4′‐bipyridine and (4,4′‐[(1E)‐ethene‐1,2‐diyl]bis[pyridine] linkers were studied in solution by means of multiple NMR experiments (1D, ROESY, and DOSY). The largest metallarectangles 10 – 12 incorporating (4,4′‐[(1E)‐ethene‐1,2‐diyl]bis[pyridine] linkers are able to host an anthracene, pyrene, perylene, or coronene molecule in their cavity, while the medium‐size metallarectangles 7 – 9 incorporating 4,4′‐bipyridine linkers are only able to encapsulate anthracene. However, out‐of‐cavity interactions are observed between these 4,4′‐bipyridine‐containing rectangles and pyrene, perylene, or coronene. In contrast, the small pyrazine‐containing metallarectangles 4 – 6 show no interaction in solution with this series of planar aromatic molecules.