Studies of Organometallic Compounds

The structures of over 800 organometallic compounds have been determined by diffraction techniques for the period covered by this Report. In the main, they have been determined by single-crystal X-t y analysis and only a limited number of compounds have been investigated by gas-phase electron diffraction (G.E.D.) and single-crystal neutron-diffraction studies. The scope and format of the chapter follow closely those of previous volumes. Hence, Section 2 contains a concise tabulation of structural data, which is intended to be comprehensive, while cross-reference tables are given in Section 3. Notes on selected structures are presented in Section 4. 

Coverage.—The literature appearing in 1980 has been scanned and compounds containing at least one metal-carbon bond have been included in Section 2. The definition of a metal in this context is taken to be any transition or inner transition element, or any member of Groups lA— VIA, with the exception of hydrogen, carbon, nitrogen, oxygen, phosphorus, and sulphur. 

5- TrimethyI-l,2,4,3,5-dithiazadiboroIidine B, jp 1.556(8), trigonal planar Trimethyl-lead azide Pb, (5p )3 2.25—2.26(10), trigonal bipyramidal (polymeric) 

Petrina, V. Petricek, L. Hummel, and A. Linek, Acta Crystallogr., Sect. B, 1980, 36, 181. 

Buss and D. Altena, unpublished results, cited by O. Glemser and R. Mews, Agnew. Chem., Int. Ed. Engl., 1980, 19, 883. 

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Mass spectroscopic studies of organometallic compounds are almost as old as the field of mass spectrometry nickel tetracarbonyl was studied by J. J. Thomson (/) and Aston (2,3) in their work on the isotope ratios of nickel. Following this early flurry of specialized interest, however, inorganic and organometallic mass spectral studies were... 

Chemical Properties. Simple molecular-orbital theory predicts that many organometallic molecules should show electronic effects similar to conjugated systems, since the electronic structure is generally expressed in terms of molecular orbitals which involve both ring and metal orbitals. The ESR spectra (Sec. III.C) provide physical evidence for this formulation however correlation between chemical reactivities and theoretical quantities, such as charge densities and localization energies, which has been of use in aromatic systems (60) has not been attempted. Indeed, very few detailed kinetic studies of organometallic compounds have been reported with which to compare theory. We consider the different classes of compounds in turn. 

R. F. Bryan X-ray and electron diffraction studies of organometallic compounds, pp. 468-500 (255). 

Raman spectroscopic studies in coordination chemistry Use of infrared and Raman spectroscopy in the study of organometallic compounds... 

Stahl, M., Pidun, U., Frenking, G. Theoretical studies of organometallic compounds. XXVII. On the mechanism of the McMurry reaction. 

During Frankland s experiment a white crystalline compound was deposited. Investigation of this ethyl zinc iodide led to his systematic study of organometallic compounds. 

Refer to something that has just happened on the program, perhaps something the previous speaker said My colleague has discussed photochemical studies of organometallic compounds. I will now discuss the photochemistry of main-group clusters, particularly the boranes. ... 

NLO transmission, and 3D microfabrication. However, there have been rather few studies of organometallic compounds at this time, especially studies in which two-photon spectra have been determined. 

The last chapter, continuing until 1992, contains a summary of structural studies of organometallic compounds, as determined by X-ray, electron, and neutron diffraction methods. 

Differential scanning calorimetry has been applied to thermodynamic studies of organometallic compounds in the solid state ( ). 

Photoelectron (PE) spectroscopy measures the binding energies of electrons in molecules. In combination with theoretical calculations, it provides a powerful insight into the detailed electronic structure of molecules. This chapter introduces basic aspects of the technique and provides a wide variety of examples where studies of organometallic compounds have been particularly fruitful. 

An overview of the recent developments in solid-state NMR applicable to studies of organometallic compounds has been presented. The rapid pace of development in this field is expected to continue - combined with new hardware, the utility of solid-state NMR in the investigation of organometallic complexes will continue to grow. Until recently, the wealth of information available from these techniques have been neglected, since the methods were often viewed as exotic or of little practical interest to anyone but physical chemists. We hope that the overview of NMR techniques presented here will convince researchers that solid-state NMR spectroscopy can be a valuable tool which can be used in their investigations. 

Davies, J. A., Multinuclear Magnetic Resonance Methods in the Study of Organometallic Compounds, in Hartley, F. R., Patai, S., The Chemistry of the Metal-Carbon Bond, Vol. 1, Wiley, Chichester 1982, pp. 813/918. 

A. Vfeldkamp and G. Frenking,/. Comput. Chem., 13, 1184 (1992). Theoretical Studies of Organometallic Compounds. III. Structures and Bond Energies of FeCH and FeCH ( = 1, 2, 3). 

V. Jonas, G. Frenking, and M. T. Reetz, OrganometalUcs, 12, 2111 (1993). Theoretical Studies of Organometallic Compounds. IV. Chelate Complexes of TiCl4 and CH3TiCl3. 

A Veldkamp and G. Frenking, /. Am. Chem. Soc., 116, 4937 (1994). Mechanism of the Enantioselective Dihydroxylation of Olefins by OSO4 in the Presence of Chiral Bases. Theoretical Studies of Organometallic Compounds. Vlll. 

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