Heterobinuclear s‐Indacene Rhodium Complexes: Synthesis and Characterization

Abstract

The monometallic complexes [Cp*M(2,(5b) were synthesized and characterized spectroscopically and in the case of complexes 1 and 5b by X-ray diffraction. C and103 Rh NMR spectroscopic studies suggest that the bonding mode of the rhodium center to the s-indacenediide ligand can be described as an inter-

Ferrocene‐Fused Acenequinones: Synthesis, Structure and Reaction Chemistry

“…In addition, the described systems maintain a very low tilt angle of the ferrocene backbone of <1.6° (herein: 1.72(4)° and 2.69(5)°), showing that Cp and Cp* moieties have similar steric impacts on 1,2‐annelated aromatics. Comparison between molecules bearing additional methyl [17] and ethyl [18] groups at the hitherto C 5 H 3 entity with torsion angles of 33.6° and 14.0°, respectively, reveal a similarly small impact.…”

A new series of zirconium metallocenes derived from partially alkylated s-indacene with potential applications in the polymerization of ethylene

“…In addition, both protons from carbon 1 appear as two different signals (doublet of doublets at 2.9 and 3.1 ppm). This spectroscopic behavior is completely different from the other mononuclear s-indacene complexes with late transition metals developed in our laboratory [27,[29][30][31][32]38], which present a singlet for both protons 5 and 7 and a broad singlet for protons 1. A possible explanation could rely on the chlorine atoms.…”

“…As part of our current interest on metallocenes derived from the fused-ring ligand s-indacene which offers the potential ability to incorporate a second catalytic site [26][27][28][29][30][31][32][33], we have reported obtaining of a new series of zirconium precatalysts using 2,6-diethyl-4,8-dimethyl-1,5-dihydro-s-indacene (Ic 0 H 2 ) and 2,6-dibutyl-4,8-dimethyl-1,5-dihydro-s-indacene (Ic 00 H 2 ) as main ligand as well as cyclopentadienyl (Cp) and pentamethylcyclopentadienyl (Cp ⁄ ) ligands. This contribution describes the general approach for the successful preparation of these molecular species were fully characterized by methods such as 1 H and 13 C NMR spectroscopic analysis, elemental analysis, and mass spectrometry.…”

Novel and Convenient Synthesis of 2,7-Dialkyl-1,8-dihydro-as-indacenes­

“…The strong electronic interactions between the metal centers in organometallic complexes make them potential model systems for organometallic polymers, which might result in a range of interesting electronic, magnetic, and optical properties, [1][2][3][4][5][6][7][8][9][10][11][12] as well as useful in homogeneous catalysis due to the presence of cooperative chemical effects. 3,[13][14][15][16][17] A suitable approach to access these type of materials is the introduction of organometallic units, such as oligomers or polymers, due to their high structural diversity and architectonic flexibility, owing to the versatility and different oxidation states of the redox centers.…”

“…26 As it has been demonstrated by our research group, the feasibility of s-indacene to be mono-or bi-deprotonated selectively is a useful strategy in the development of a rational syn-thetic stage route, which allows the preparation of heterobimetallic and oligomeric complexes. 3,4,23,[27][28][29] It is expected that the increase in the number of organometallic units will lead to systems with smaller HOMO-LUMO gap (<0.5 eV), which have shown a variety of unusual optoelectronic properties 30 and multielectron-transfer behavior 31 that makes these systems attractive targets to study the electron-transfer phenomena, as well as molecular electronics applications. 32,33 However, the development of this fused polycyclic bridging ligand chemistry has been rather slow, apart from the nonsubstituted dihydro-s-indacene 34 and the stable 1,3,5,7-tetra-tert-butyl-s-indacene.…”