Theoretical and Spectroscopic Studies

A detailed spectroscopic and theoretical study of the conformation of dioxolanes 1 has appeared <96T8275>, and a theoretical study has shown that the anomeric effect explains the non-planarity of 1,3-dioxole <96JA9850>. The tetraalkynyldioxolanone 2 has been prepared and its structure and reactivity studied <96HCA634>. Both enantiomers of the chiral glycolic acid equivalent 3 can be prepared from D-mannitol <96HCA1696>, and lipase-mediated kinetic... 

Spectroscopic, and Theoretical Studies on MoleculEu- Phosphorus Oxides and Oxide Sulfides J. Clade, F. Frick, and M. Jansen... 

Baldwin, M. J., P. K. Ross, J. E. Pate, Z. Tyeklar, K. D. Karlin, and E. I. Solomon. 1991. Spectroscopic and Theoretical Studies of an End-On Peroxide-Bridged Coupled Binuclear Cooper(II) Model Complex of Relevance to Active Sites in Hemocyanin and Tyrosinase. J. Am. Chem. Soc. 113, 8671. 

Zhang, L.Z., Sun, W. and Cheng, P. (2003). Spectroscopic and theoretical studies of quantum and electronic confinement effects in nanostructured materials. Molecules 8, 207-222... 

P. Barta, P. Dannetun, S. Stafstrom, M. Zagorska, and A. Pron, Temperature evolution of the electronic band structure of the undoped and doped regioregular analog of poly(3-alkylthio-phenes) a spectroscopic and theoretical study, J. Chem. Phys., 100 1731-1741, 1994. 

S. Jarmelo, N. Maiti, V. Anderson, P. R. Carey, and R. Fausto, Ca H bond stretching frequency in alcohols as a probe of hydrogen bonding strength A combined vibrational spectroscopic and theoretical study of n [1 Djpropanol. J. Phys. Chem. A 109, 2069 2077 (2005). 

These complexes are effective catalysts in epoxidation reactions with H2O2 and alkyl hydroperoxides. Several detailed mechanistic studies have been carried out in particular, it has been shown that, when the alkyl chain contains a double bond, no autoepoxidation is observed both in the solid state and in solution. Nevertheless, if f-BuOOH is added, the epoxidation of the olefinic moiety immediately takes place. Therefore, it has been suggested that these complexes are not the active species in the oxygen transfer step to the substrate, but they behave as catalysts for the primary peroxidic oxidant. On the basis of kinetic, spectroscopic and theoretical studies, the authors provided a mechanism, whose key steps are sketched in Scheme 12. In this context a major role appears to be played by the fluxionality of the particular ligands used . ... 

Spectroscopic, and Theoretical Studies on Molecular Phosphorus Oxides and Oxide Sulfides... 

Mulliken attributed the strong absorption band of the system to the excitation of the ground-state complex to the CT state with the aromatic molecule acting as the electron donor and the iodine as the acceptor, that is, Bz+ I2. Several spectroscopic and theoretical studies have predicted that the Bz I2 ground state has a C(,v axial structure with the 1—I bond being perpendicular to the benzene molecular plane. The heat of formation of this complex in the gas phase was determined by spectrometric methods to be on the order of 2-3 kcal/mol and our ab initio calculations support these values. 

C NMR spectroscopic and theoretical studies (DFT, ab initio, IGLO) of a series of cycloacylium ions were performed by Prakash et al.577 The study showed that the cycloalkyl groups have little effect on the shift of the carbocationic carbon. Furthermore, charge calculations showed that the delocalization into the cycloalkyl group is greater than in the protonated carboxylic acid (carboxonium ion), where two oxygen atoms participate in delocalization. 

Heterostannenes, preparation and characteristics, 3, 870 Heterosubstituted arenes, metallation, 9, 17 Hexaaryldiplumbanes, preparation, 3, 887 Hexabutyldistannane, preparation, 3, 856 Hexacarbenes, in cobalt(III) complexes, 7, 19 Hexacarbonyl complexes, with molybdenum kinetics and reactivity, 5, 395 photochemistry, 5, 393 solid-support studies, 5, 394 spectroscopic and theoretical studies, 5, 392 Hexadentate iV-substituted triazacyclononane, synthetic applications, 1, 70... 

A considerable number of crystal structures of type I copper sites in proteins are now available, so there may be no particular advantage in the synthetic model approach to prove the coordination structure of type I. Yet, inorganic chemists still have an opportunity to utilize the spectroscopic and structural bases established by model studies to understand the precise electronic structure of type I copper. One should keep in mind that the generally accepted interpretation derived from spectroscopic and theoretical studies on the proteins (47-49) has not been definitely proved experimentally. A systematic comparison of a series of copper(II) thiolate complexes having an unusual distorted coordination structure is required for a conclusive description of the electronic structure of the type I copper. The synthetic approach is ultimately the most adequate way to clarify how the ligand donors and geometry affect the electronic property and function of type I copper as an electron transfer center. 

RECENT SYNTHETIC, STRUCTURAL, SPECTROSCOPIC, AND THEORETICAL STUDIES ON MOLECULAR PHOSPHORUS OXIDES AND OXIDE SULFIDES... 

Cluster X-Ray Synthesis Reagents and conditions Yield (%) Spectroscopic and theoretical studies ... 

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