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Cp Ring (cp + ring)
Selected AbstractsReactions of Pendant Boryl Groups in Cp,Metal Complexes: Heterocyclic Ring Annelation in a CpIr SystemEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2008Christoph Herrmann Abstract Treatment of (cod)IrCl dimer with Li(allyl)cyclopentadienide gave (C5H4,CH2,CH=CH2)Ir(cod) (11). At 100 °C, 11 isomerizes cleanly into its ring-conjugated (trans -CH3,CH=CH,C5H4)Ir(cod) isomer (13). Subsequent addition of HB(C6F5)2 results in the formation of a product (16) that contains an annelated five-membered borata heterocycle at the Cp ring. This is probably formed by means of a reaction sequence involving regioselective hydroboration, followed by an electrophilic substitution reaction at the Cp ring by the strongly Lewis acidic ,B(C6F5)2 group, in which the iridium metal base acts as the proton abstractor. Products 13 and 16 were characterized by X-ray diffraction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] (,5 -Cyclopentadienyl)[(1,2,3,4,4a,10a-,)-1-methylthianthrene]iron(II) hexafluoridophosphate acetone 0.33-solvateACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2009Arthur D. Hendsbee The title complex salt, [Fe(C5H5)(C13H10S2)]PF6·0.33C3H6O, obtained from an acetone,diethyl ether,dichloromethane mixture at 280,(2),K, has three cationic molecules (A,C), three hexafluoridophosphate counter-anions and one acetone solvent molecule in the asymmetric unit. Two of the three cations contain FeCp (Cp is cyclopentadienyl) inside the fold of the heterocycle. The dihedral angles between the planes of the external (complexed and uncomplexed) benzene rings in the thianthrene molecule are 146.5,(2)° for FeCp-out-of-fold molecule A, and 139.0,(3) and 142.5,(2)° for the two FeCp-in-fold molecules B and C, respectively. The complexed Cp and benzene rings in each molecule are almost parallel, with a dihedral angle between the planes of 0.2,(5)° for molecule A, 2.8,(5)° for B, and 2.19,(4) and 6.86,(6)° for the disordered Cp ring in C. [source] Bromido(,5 -carboxycyclopentadienyl)dinitrosylchromium(0) and (,5 -benzoylcyclopentadienyl)bromidodinitrosylchromium(0)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2009Yu-Pin Wang In the structures of each of the title compounds, [CrBr(C6H5O2)(NO)2], (I), and [CrBr(C12H9O)(NO)2], (II), one of the nitrosyl groups is located at a site away from the exocyclic carbonyl C atom of the cyclopentadienyl (Cp) ring, with twist angles of 174.5,(3) and 172.5,(1)°. The observed orientation is surprising, since the NO group is expected to be situated trans to an electron-rich C atom in the ring. The organic carbonyl plane is turned away from the Cp ring plane by 5.6,(8) and 15.2,(3)°in (I) and (II), respectively. The exocyclic C,C bond in (I) is bent out of the Cp ring plane towards the Cr atom by 2.8,(3)°, but is coplanar with the Cp ring in (II); the angle is 0.1,(1)°. [source] Highly Efficient Redox Isomerization of Allylic Alcohols at Ambient Temperature Catalyzed by Novel Ruthenium,Cyclopentadienyl Complexes,New Insight into the MechanismCHEMISTRY - A EUROPEAN JOURNAL, Issue 20 2005Belén Martín-Matute Dr. Abstract A range of ruthenium cyclopentadienyl (Cp) complexes have been prepared and used for isomerization of allylic alcohols to the corresponding saturated carbonyl compounds. Complexes bearing CO ligands show higher activity than those with PPh3 ligands. The isomerization rate is highly affected by the substituents on the Cp ring. Tetra(phenyl)methyl-substituted catalysts rapidly isomerize allylic alcohols under very mild reaction conditions (ambient temperature) with short reaction times. Substituted allylic alcohols have been isomerized by employing Ru,Cp complexes. A study of the isomerization catalyzed by [Ru(Ph5Cp)(CO)2H] (14) indicates that the isomerization catalyzed by ruthenium hydrides partly follows a different mechanism than that of ruthenium halides activated by KOtBu. Furthermore, the lack of ketone exchange when the isomerization was performed in the presence of an unsaturated ketone (1 equiv), different from that obtained by dehydrogenation of the starting allylic alcohol, supports a mechanism in which the isomerization takes place within the coordination sphere of the ruthenium catalyst. [source] Catalytic Trimerization of Ethylene with Highly Active Half-sandwich Titanium Complexes Bearing Pendant p -Fluorophenyl GroupsCHINESE JOURNAL OF CHEMISTRY, Issue 10 2006Chen Wang Abstract Two new complexes [,5 -C5H4CMe2 -(p -fluorophenyl)]TiCl3 (1) and [,5 -C5H4C(cyclo-C5H10)-(p -fluoro-phenyl)]TiCl3 (2) were synthesized and characterized. Their activities and selectivities for trimerization of ethylene were investigated. The introduction of fluorine atom greatly weakened the arene coordination, but this disadvantageous factor can be eliminated by introduction of a bulky substituent, such as cyclo-C5H10, to the bridging carbon linked to the Cp ring. The combinative effect of the fluorine substitute and the bridging unit can make complex 2 as a highly active and selective catalyst for ethylene trimerization. Its productivity and selectivity for 1-hexene can reach 1024.0 kg·mol,1·h,1 and 99.3% respectively. [source] The ansa -zirconocene [bis(,5 -cyclopentadienyl)phenylphosphine]dichloridozirconium(IV)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2010Susanne Büschel In the title compound, [Zr(C16H13P)Cl2], the geometry at the metal atom is distorted tetrahedral; the Cl,Zr,Cl angle is 101.490,(16)° and the cyclopentadienyl (Cp) centroids subtend an angle of 122.63,(3)° at the Zr atom. The P atom lies 0.474,(3) and 0.496,(3),Ĺ out of the planes of the Cp rings. The C,P,C angle of 91.42,(7)° reflects the pincer effect of the two Cp rings. Three C,H...Cl, one C,H...P, one C,H..., and one Cl...P interaction link the molecules to form thick layers parallel to the bc plane. [source] | ||||||||||