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Treatment of {eta(5):eta(1)[2-(di-tert-butylphosphanyl-P)ethyl]cyclopentadienyl}cobalt(I) chloride (5) with methylenecyclopropane (3) or bicyclopropylidene (4), as well as with their spirocyclopropanated analogues methylenespiropentane (7), cyclopropylidenespiropentane (10), or 7,7'-bi(dispiro[2.0.2.1]heptylidene) (15) in the presence of sodium amalgam at -50 degrees C, furnished the stable cobalt complexes 6, 9, 8, 11, and 16, respectively, in 72, 83, 84, 86, and 54 % isolated yield, respectively. The complexes 14 and 16 were also obtained by ligand exchange of the ethene complex {eta(5):eta(1)[2-(di-tert-butylphosphanyl-P)ethyl]cyclopentadienyl}(eta(2)-ethene)cobalt(I) (12) with 13 and 15 in 79 and 52 % yield, respectively. The X-ray crystal-structure analyses of complexes 9, 14, and 16, as well as the NMR-spectroscopic data of all complexes, reveal that they can be regarded as linear and branched cobalta[n]triangulanes. The thermal stability of complexes 6, 8, and 9 up to 109, 145, and 160 degrees C was determined by differential thermal analysis-thermogravimetry (DTA-TG) analysis.

Oxidation of [Yb(OArR)2(THF)3] (OArR = OC6H2–2,6-tBu2-4-R; R = H, Me, tBu) with HgX2 or with (CH2X)2 (X = Cl, Br, I) in THF yields [Yb(OArR)2X(THF)2], whilst [Yb(OArMe)2Cl(THF)2] was also obtained by oxidation of the appropriate Yb(II) aryloxide with C2Cl6 in THF. An X-ray crystal structure determination has shown [Yb(OArMe)2I(THF)2] to be a five coordinate monomer, in which ytterbium has distorted square pyramidal stereochemistry with mutually trans OArMe and THF ligands in the square plane and an apical iodide. Attempts to grow single crystals of [Yb(OArH)2Cl(THF)2] yielded [Yb(OArH)2OH(THF)]2, shown to be an hydroxo-bridged dimer with five-coordinate ytterbium by X-ray crystallography. Organoamido- und Aryloxo-Lanthanoide. 26 Synthese von Bis(aryloxo)halogenoytterbium(III)-Komplexen: [Yb(OAr)2X(THF)2] (X = Cl, Br, I, OAr = OC6H2–2,6-tBu2-4-R; R = H, Me, tBu) und die Kristallstrukturen von [Yb(OC6H2-2,6-tBu2-4-Me)2I(THF)2] und [Yb(OC6H3-2,6-tBu2)2OH(THF)]2 Die Umsetzung von [Yb(OArR)2(THF)3] (OArR = OC6H2-2,6-tBu2-4-R; R = H, Me, tBu) mit HgX2 (X = Cl, Br, I) oder mit (CH2X)2 in THF fuhrt zu [Yb(OArR)2X(THF)2]. [Yb(OArMe)2Cl(THF)2] ist ebenso durch Oxidation des entsprechenden Yb(II)-Aryloxides mit C2Cl6 in THF erhaltlich. Nach Auskunft einer Einkristallstrukturanalyse liegt [Yb(OArMe)2I(THF)2] als Monomer mit funffach koordiniertem Ytterbium vor. Die Anordnung der Liganden um das Ytterbiumatom entspricht einer verzerrten quadratischen Pyramide, mit trans-standigen OArMe- und THF-Liganden in der Basisflache und dem Iod-Atom in der apikalen Position. Versuche, Einkristalle von [Yb(OArH)2Cl(THF)2] zu zuchten, fuhrten zur Bildung von [Yb(OArH)2OH(THF)]2, in denen eine OH-verbruckte dimere Einheit vorliegt, so dass Ytterbium ebenfalls die Koordinationszahl 5 erreicht.

Reaction of [Yb(OAr)2(THF)3] (OAr = OC6H2-2,6-tBu2-4-R; R = H, Me, tBu) with perfluorodecalin in THF at room temperature results in C–F activation and formation of the first heteroleptic aryloxofluorolanthanoid complexes, [Yb(OAr)2F(THF)]2. Oxidation of bis(cyclopentadienyl)ytterbium(II) with perfluoro(methylcyclohexane) or perfluorodecalin in DME surprisingly gives unsolvated [YbCp2F]3. The analogous reaction of bis(methylcyclopentadienyl)ytterbium(II) yields unsolvated [Yb(MeCp)2F]4, whilst in THF, the oxidation provides [Yb(MeCp)2F(THF)]2. Treatment of [YbCp2F(THF)]2 with triphenylphosphane oxide gives [YbCp2F(OPPh3)]2. X-ray structure determinations revealed [Yb(OAr)2F(THF)]2 (R = H or tBu) to be centrosymmetric fluoride-bridged dimers with five-coordination for ytterbium. Examination of the structures of the cyclopentadienyl complexes showed that [YbCp2F]3 is trimeric with formal eight-coordination for ytterbium and a planar (YbF)3 ring, whereas [Yb(MeCp)2F]4 is an eight-coordinate tetramer having a puckered (YbF)4 ring with F–Yb–F angles of ca. 90° and Yb–F–Yb angles close to 180° [178.9(4), 168.4(3)°]. Both [Yb(MeCp)2F(THF)]2 and [YbCp2F(OPPh3)]2 are nine-coordinate fluoride-bridged dimers.

The X-ray crystal structures of Hg(C6F4X-p)2 (X = NH2, OMe, or Me) show the compounds to have almost linear C–Hg–C stereochemistry (X = NH2, 176.3(4)°; X = OMe, 179.5(2)°; X = Me, 176.3(2)°), and the two tetrafluoroaryl rings rotated ca. 52–62° with respect to each other. Substantial conjugation of NH2 and OMe groups with the aromatic rings is evident from N–C and O–C(Ar) distances. For X = NH2 or OMe, two weak N(O)–Hg coordination interactions per mercury lead to a two dimensional supramolecular chain structure containing pairs of π-stacked aromatic rings at near van der Waals contact distances rotated at 62.2° (X = NH2) or 52.9° (X = OMe) to each other. In Hg(C6F4Me-p)2, which does not have potential donor atoms, no supramolecular structure is obtained, the molecules being laterally displaced from one another. Organoquecksilber-Verbindungen. 33 Die Kristallstrukturen von Hg(C6F4X-p)2 (X = NH2, OMe, Me) – Zwei Beispiele fur supramolekulare Lewis-Saure-Base-Komplexe In den Kristallstrukturen von Hg(C6F4X-p)2 (X = NH2, OMe, or Me) liegen nahezu lineare C–Hg–C-Gruppen vor (X = NH2, 176,3(4)°; X = OMe, 179,5(2)°; X = Me, 176,3(2)°); die beiden Tetrafluoroaryl-Ringe sind um 52–62° gegeneinander verdreht. Aus den Abstanden N–C und O–C(Ar) ergibt sich eine deutliche Konjugation der NH2- und OMe-Gruppen mit den aromatischen Ringen. Zwei schwache koordinative N(O)–Hg-Wechselwirkungen pro Hg-Atom ergeben fur X = NH2 bzw. OMe eine zweidimensionale supramolekulare Kettenstruktur aus Paaren von uber π-Wechselwirkungen gestapelten aromatischen Ringen mit nahezu van der Waals-Kontakten; die aromatischen Ringe sind um 62,2° (X = NH2) bzw. 52,9° (X = OMe) gegeneinander verdreht. Hg(C6F4Me-p)2 hat keine potentiellen Donor-Atome; folgerichtig wird keine supramolekulare Struktur beobachtet, die Molekule liegen seitwarts nebeneinander.

The complexes [K(H2O)2LnL2] (Ln = La or Nd; L = 1,2-benzenedisulfonate) and [K(H2O)Yb(H2O)4L2] were initially isolated fortuitously from attempts to prepare the corresponding Ln2L3 complexes from Ln2O3 and H2L in water. Indeed the bulk products from these reactions have the composition Ln2L3. Subsequently, deliberate syntheses by reacting equimolar amounts of Ln2L3 with K2L in water gave the complexes in good yield. X-ray crystal structures of [K(H2O)2LnL2] (Ln = La or Nd) showed the complexes to be isostructural with a two dimensional polymeric network structure in which LnL2 units are linked into chains crosslinked by potassium ions. Each Ln is nine coordinate with solely sulfonate oxygen donor atoms. Between adjacent lanthanoid ions there are three different types of sulfonate bridges and two examples of each. Most noteworthy is highly unsymmetrical bridging through μ-η2-sulfonate oxygen atoms. Consequently, one Ln–O bond is ca. 0.5 A longer than the other eight. Potassium is nine-coordinate with seven sulfonate oxygen atoms and two aqua ligands, and surprisingly is much longer than . Pairs of potassium ions are linked by two μ-η2-sulfonate oxygen atoms, which are unsymmetrically bridging. The structure of [K(H2O)Yb(H2O)4L2] comprises discrete tetranuclear units containing two independent ytterbium ions, each coordinated by four water molecules and two chelating (via seven membered rings) disulfonate ligands, and two potassium ions, each coordinated by six sulfonate oxygen atoms and a water molecule. For each potassium, four of the coordinated sulfonate oxygen atoms are from sulfonate ligands bonded to one ytterbium atom and two from sulfonate ligands attached to the other ytterbium atom. In contrast to the Nd and La complexes, is shorter than . Synthese und Kristallstrukturen von Kalium–Lanthanoid(III) Komplexen mit 1,2-Benzoldisulfonat als Liganden Bei Versuchen zur Synthese der Verbindungen Ln2L3 aus Ln2O3 und H2L (Ln = La, Nd, Yb; L = 1,2-Benzoldisulfonat) in Wasser wurden auch die Komplexe [K(H2O)2LnL2] (Ln = La, Nd) und [K(H2O)Yb(H2O)4L2] erhalten. Die analytische Zusammensetzung der Produkte entspricht tatsachlich Ln2L3; die neuen Komplexe wurden daraufhin aus Ln2L3 und K2L in guter Ausbeute gewonnen. Nach Ausweis von Einkristallstrukturanalysen sind die Komplexe [K(H2O)2LnL2] (Ln = La, Nd) isotyp, sie bilden ein zweidimensionales polymeres Netzwerk, in dem LnL2-Einheiten zu Ketten angeordnet sind, die durch Kaliumatome miteinander verknupft sind. Die Zentralteilchen Ln3+ sind neunfach von einzelnen Sulfonat-Sauerstoffatomen koordiniert. Zwischen benachbarten Lanthanoidionen gibt es drei verschiedene Typen von Sulfonatbrucken. Bemerkenswert ist die sehr unsymmetrische Brucke zwischen μ-η2-Sulfonat-Sauerstoffatomen. Folglich ist eine Ln–O-Bindung ca. 0.5 A langer als die anderen acht. Kalium ist neunfach von sieben Sulfonat-Sauerstoffatomen und zwei Wassermolekulen koordiniert, uberraschenderweise ist viel langer als . Die Kaliumionen sind paarweise uber zwei unsymmetrisch verbruckende μ-η2-Sulfonat-Sauerstoffatome miteinander vernetzt. Die Kristallstruktur von [K(H2O)Yb(H2O)2L2] besteht aus vierkernigen Einheiten, die zwei Kalium- und zwei voneinander unabhangige Ytterbiumatome enthalten, von denen jedes von vier Wassermolekulen und zwei chelatisierenden Disulfonatliganden koordiniert ist. Die beiden Kaliumatome sind von sechs Sulfonat-Sauerstoffatomen und einem Wassermolekul umgeben. Vier der an Kalium koordinierten Sauerstoffatome gehoren Sulfonatliganden an, die an ein Ytterbiumatom gebunden sind, zwei gehoren zu Sulfonatliganden, die an das andere Ytterbiumatom gebunden sind. Im Gegensatz zu den Nd- und La-Komplexen ist hier kurzer als .

(Di-tert-butylphosphanyl-P-ethyl)cyclopentadienylcobalt(I) complexes 1 and 2 were treated with 3,3-disubstituted cyclopropenes to give isoprene and vinylcarbene complexes. The diphenylvinylcarbene complex reacted with tert-butylphosphaethyne to give unusual coupling products.

Reaction of YbCp2(DME) (Cp=cyclopentadienyl; DME=1,2-dimethoxyethane) with perfluorodecalin or perfluoro(methylcyclohexane) in THF yields [YbCp2F(THF)]2. These are the first examples of C–F activation of saturated perfluorocarbons by a lanthanoid organometallic. The X-ray crystal structure of [YbCp2F(THF)]2 (monoclinic, P21/c, a=7.9901(12), b=20.411(4), c=8.5957(12) A; β=104.70(2)°, Z=2, R1=0.0495, for 1107 observed data) shows the complex to be dimeric with bridging fluorides and formal nine coordination for ytterbium. YbCp2F has also been obtained by oxidation of YbCp2(DME) with AgF or HgF2.

Reaction of YbCp2(DME) (Cp  cyclopentadienyl; DME = 1,2-dimethoxyethane) with MCl2 (M  Hg, Cd, Zn, Pb, Sn, Cu, Pd, or Co) or MCl (M  Ag, Cu or Tl) in tetrahydrofuran (THF) gives the metal M and YbCp2Cl(THF)0.5, generally in excellent yield, with small amounts of TlCp and CoCp2 also detected from TlCl and CoCl2 respectively. Similarly, YbCp2X(THF) (X  Br or l) and YbCp2Cl(DME)0.5 have been prepared in good yields by analogous oxidation with suitable mercury(II) halides. However YbCp2(DME) and FeCl3 yield ferrocene. In simpler syntheses. YbCp2X(THF)n (X  Cl, n = 0.5; X  Br or I, n = 1) have been obtained by reactions of YbCp2(DME) with C2Cl6 or (CH2X)2 (X  Br or l) in THF, and (YbCp2X)2 by analogous reactions of unsolvated YbCp2 in petroleum ether. The X-ray crystal structure of YbCp2l(THF) (monoclinic, P2 1 /c, a = 8.147(1), b = 13.788(2), c = 14.149(3) A , β = 105.56(1)°, Z = 4, R = 0.042 , for 2324 observed data) shows the complex to be monomeric with formal eight coordination for ytterbium, and with a pseudo-tetrahedral array of the centroids of the Cp rings, oxygen, and iodine ( YbC > 2.565 A , YbO 2.311(5) A , Yb = 12.9316(7) A ).

Bis(cyclopentadienyl)samarium(II) has been shown to be insoluble in thf : ether mixtures, hence it cannot be isolated as a soluble product from the reaction of samarium with HgCp2 in thf : ether.