S. S. Shapovalov

Stannylene complexes of manganese, iron, and platinum

A number of stannylene complexes with different M: Sn ratios were obtained using various metals and substituents at the tin atom. The structures of the complexes were examined. A reaction of CpMn(CO)2THF with (Ph4As)+(SnCl3)− gave the ionic complex [Ph4As]+[CpMn(CO)2SnCl3]− (I). The action of C6F5MgBr on the complex C5H5Mn(CO)(NO)SnCl3 produced C5H5Mn(CO)(NO)Sn(C6F5)3 (II). Replacement of the Cl ions in the complex [CpFe(CO)2]2SnCl2 by phenylacetylenide groups gave rise to the neutral complex [CpFe(CO)2]2Sn(C≡CPh)2 (III). A reaction of (Dppm)PtCl2 (Dppm is 1,1-bis(diphenylphosphino)methane) with SnCl2 · 2H2O in the presence of diglyme yielded the ionic complex [η3-CH3O(CH2)2O(CH2)2OCH3)SnCl]+[(η 2-Dppm)Pt(SnCl3)3]− (IV). Transmetalation in a reaction of [(Dppe)2CoCl][SnCl3] · PhBr (Dppe is 1,2-bis(diphenylphosphino)ethane) with (Dcpd)PtCl2 (Dcpd is dicyclopentadiene) in the presence of SnCl2 afforded the ionic complex [Pt(Dppe)2]3[Pt(SnCl3)5]2 (V). Structures I–V were identified by X-ray diffraction. In these structures, the formally single bonds between the atoms of transition metals M (Mn, Fe, and Pt) and Main Group heavy elements (Sn and P) having vacant d orbitals are appreciably shortened. The M-Sn bond length in complexes II and III are virtually independent of the substituents at the tin atom and the Pt-Sn bond length in complexes IV and V is virtually independent of the Pt: Sn ratio.

Cymantrenecarboxylate complexes of nickel(II) and cobalt(II)

Reactions of cymantrenecarboxylic acid (CO)3MnC5H4COOH (CymCOOH) with Ni(II) and Co(II) pivalates in boiling THF followed by extraction of the products with diethyl ether or benzene and treatment with triphenylphosphine gave the binuclear complexes LM(CymCOO)4ML (M = Ni (I) and Co (II); L = PPh3). Treatment of the benzene extract of the intermediate cobalt cymantrenecarboxylate with 2,6-lutidine (L’) yielded the trinuclear complex L’Co(CymCOO)3Co(CymCOO)3CoL’ (III). Complex I is antiferromagnetic; μeff decreases from 3.7 to 0.9 μB in a temperature range from 300 to 2 K. Structures I-III were identified using X-ray diffraction. The frameworks of complexes I and II are like Chinese lanterns, having four carboxylate bridges and axial ligands L (Ni-P, 2.358(1) Å; Co-P, 2.412(2) Å). The metal atoms are not bonded to each other (Ni…Ni, 2.7583(9) Å; Co…Co, 2808 (2) Å). In complex III, either terminal Co atom is coordinated to one ligand L’ (Co-N, 2.059(2) Å). The Co atoms form a linear chain showing no M-M bonds (Co…Co, 3.346(1) Å), in which either terminal Co atom is linked with the central Co atom by three carboxylate bridges (on average, Cocentr-O, 2.164 Å; COterm-O, 2.094 Å). In one of three carboxylate groups, only one carboxylate O atom serves as a bridge, while the other is bonded to the terminal Co atom only (Coterm-O, 2.094 and 2.389 Å); so this carboxylate group is a bridging and chelating ligand.

Synthesis and molecular structures of cymantrenecarboxylate derivatives of titanium(IV) and vanadium(III) cyclopentadienyl complexes and of copper(II) and manganese(II) lutidine complexes

The reactions of dimethyltitanocene borohydride and vanadocene with cymantrenecarboxylic acid CymCOOH gave the monomer (C5H4Me)2Ti(OOCCym)2 (I) and dimer (C5H5)V(OOCCym)4V(C5H5) (II), respectively. Treatment of Cu(II) cymantrenylcarboxylate with excess lutidine gives the monomer (C7H9N)2Cu(COOCym)2 (III). The reaction of lutidine with a mixture of Cu(II) and Mn(II) bis-cymantrenecarboxylates affords the heterometallic trinuclear complex (C7H9N)Cu(OOCCym)3Mn(OOCCym)3Cu(C7H9N) (IV). The structures of I–IV were established by X-ray diffraction. In I and III, the cymantrenecarboxylate groups are terminal and in II and IV, they are bridging, which is also manifested as characteristic OCO stretching bands in the IR spectra.

Dicarbonylcyclopentadienyltellurophenyliron complexes as ligands

The reaction of CpFe(CO)2TePh (I) with ferricinium hexafluorophosphate as an oxidant affords ionic complex {[CpFe(CO)2]2(μ-TePh)}+PF6− (II) with the simultaneous formation of diphenylditellurium. The decarbonylation of compound II by Me3NO followed by the addition of complex I affords trinuclear complex {[CpFe(CO)2(μ-TePh)]2Fe(CO)Cp}PF6 (III). The corresponding tetrafluoroborate (IV) is synthesized similarly. The heating of compound I with PPh3 gives CpFe(CO)(PPh3)TePh (V) that reacts with ionic complex [CpMn(CO)2(NO)]PF6 (VI) to form binuclear heterometallic ionic complex [CpFe(CO)(PPh3)(μ-TePh)Mn(CO)(NO)Cp]PF6 (VII). A similar reaction of Cp′Fe(CO)2TePh (Cp′ is methylcyclopentadienyl) with compound VI affords heterometallic [Cp′Fe(CO)2(μ-TePh)Mn(CO)(NO)Cp]PF6 (VIII). The structures of compounds II, IV, VII, and VIII are determined by X-ray diffraction analysis (CIF files CCDC 963285, 963286, 963288, and 963289, respectively).

Phenyltellurolate-bridged heterometallic complexes combining rhenium tricarbonyl with (dicarbonyl)(cyclopentadienyl)iron or bis(diphenylphosphino)ethaneplatinum

A reaction of CpFe(CO)2TePh with Re(CO)3(THF)2Cl in THF gave the heterometallic complex [CpFe(CO)2(μ-TePh)]2Re(CO)3Cl (I). Either iron atom in complex I is linked to rhenium by only one Phenyltellurolate bridge. When treated with (Dppe)Pt(TePh)2, complex I underwent transmetalation by elimination of two CpFe(CO)2TePh molecules followed by the formation of the heterometallic chelate complex (Dppe)Pt(μ-TePh)2Re(CO)3Cl (II). Complex II was also obtained in an independent way from (Dppe)Pt(TePh)2 and Re(CO)3(THF)2. Structures I and II (II · MePh and II · CDCl3) were identified by X-ray diffraction (CIF file, CCDC nos. 981467, 981468, and 981469, respectively).

Heterometallic heterochalcogenmethylarsenide clusters: Synthesis, molecular structures, and thermolysis

Reactions of the arsinechalcogenide complexes [Fe3(μ3-X)(μ3-AsCH3)(CO)9] (X = Se (Ia) or Te (Ib)) with (PPh3)2Pt(PhC≡CPh) (transmetalation reaction) and Cp2Cr2(SCME3)2S (Cp = π-C5H5) (photochemical reaction) gave the heterometallic (heterochalcogen)(methylarsine) clusters [(PPh3)2Pt(μ3-X)(μ3-AsCH3)Fe2(CO)6] (II and III, respectively), as well as Fe3(μ3-X)(μ3-AsCH3)(CO)8(C5H5)2Cr2(μ3-S)(μ2-StBu)2 (IV and V, respectively). The structures of complexes II, IV, and V were determined by X-ray diffraction analysis. Thermolysis of all the complexes yielded no metal carbides or oxides.

Iron cyclopentadienyl(triphenylphosphine)carbonylphenyl telluride adducts with manganese, tungsten, and rhodium complexes

The reactions of CpFe(CO)(PPh3)TePh (I) with CpMn(CO)2(THF), W(CO)5(THF), and [Cp*RhCl2]2 gave heterometallic adducts CpFe(CO)(PPh3)(µ-TePh)CpMn(CO)2 (II), CpFe(CO)(PPh3)(µ-TePh)W(CO)5 (III), and CpFe(CO)(PPh3)(µ-TePh)RhCl2Cp* (IV). The structures of II, III, and IV · 3CDCl3 (CIF files CCDC nos. 063654, 1063655, 1038123) were studied by X-ray diffraction. In all complexes, metal atoms are connected by only one tellurophenyl bridge. All M → Te bonds are substantially shortened with respect to the sum of the covalent radii owing to the additional M → Te dative interactions.

Neutral and monocationic dinuclear (carbonyl)(cyclopentadienyl)(phenylchalcogenate) iron complexes of the general formulas [(RC5H4)Fe(CO)EPh]2 and [(RC5H4)Fe(CO)EPh]2PF6 (E = S or Te; R = H or Me): Synthesis, molecular structures, and EPR spectra

Heating of the compounds (RC5H4)Fe(CO)2TePh (R = H (I) and Me (II)) in heptane afforded the dinuclear complexes [(RC5H4)Fe(CO)TePh]2 (III and IV, respectively). By oxidation with Fc+PF6−, these complexes were transformed into the paramagnetic cationic complexes [(RC5H4)Fe(CO)TePh]2PF6 (V and VI, respectively). Structures III–V and [(C5H5)Fe(CO)SPh]2PF6 (VII) were characterized by X-ray diffraction.

(Dicarbonyl)(π-cyclohexadienyl)iron iodide, trichlorostannate, and tris(cymantrenecarboxylato)stannate: Synthesis and molecular structures

A reaction of [(η5-C6H7)Fe(CO)3]BF4 with KI in acetone gave brown crystals of the complex [(η5-C6H7)Fe(CO)2]I (I), which was treated with SnCl2 in THF to form orange crystals of the complex [(η5-C6H7)Fe(CO)2]SnCl3 (II). A reaction of complex II with potassium cymantrenecarboxylate ((CO)3MnC5H4COOK, or CymCOOK) in THF yielded yellow crystals of the complex [(η5-C6H7)Fe(CO)2]Sn(CymCOO)3 (III). Structures I–III were identified using X-ray diffraction. The fragment (η5-C6H7)Fe(CO)2 in complexes I–III remains virtually unchanged. The Fe-I bonds in complex I (2.6407(3) Å) and the Fe-Sn bonds in complexes II and III (2.4854(3) and 2.4787(4) Å, respectively) are appreciably shorter than the sum of the covalent radii of the corresponding elements, probably because of an additional dative interaction of the d electrons of iron with the vacant d orbitals of iodine or tin.

Unexpected stabilization of the heterocyclic form of oxidized dithizone: Synthesis and molecular structures of chromium and tungsten 5-mercapto-2,3-diphenyltetrazolium pentacarbonyls

New chromium and tungsten pentacarbonyl complexes with 5-mercapto-2,3-diphenyltetrazole coordinated through the sulfur atom (Cr-S, 2.4655(7) Å; W-S, 2.5755(13) Å) were synthesized and structurally characterized.