Lithium salts theoretical studies

Compared with metal enolates, there have been very few reports on the direct structural analysis and theoretical studies of ynolates. An X-ray crystal structure of a vanadium complex of lithium ynolate with a porphyrinogen ligand (56) is reported. This metal complex was incidentally formed from VCl3(THF)3 with tetralithium salt of the octaethyl-porphyrinogen ligand. In this complex, the lithium cation seems to interact with the 7T-electrons of the ynolate. The four atoms of the ynolate group in 56 are not collinear due to a partial sp character of the group in this complex. 

S. Tsuzuki, K. Hayamizu, S. Seki, J. Phys. Chem. B 2010, 114, 16329-16336. Origin of the low viscosity of [emim][(FS02)2N] ionic Uquid and its lithium salt mixture Experimental and theoretical study of self-diffusion coefficients, conductivities, and intermolecular interactions. 

The theoretical studies of the SEI-electrolyte interface are rare [50], while ion transport in electrolytes doped with lithium salts has received significant attention in the form of MD simulations [52, 53, 56, 61, 64, 70, 124-126], ab initio simulations [51, 127], and QC studies [29, 124, 126, 128-134], The DFT studies of EC-based electrolyte interactions with a graphite anode were recently reviewed by... 

Rhodium-catalyzed carbonylation of methanol is known as the Monsanto process, which has been studied extensively. From the reaction mechanism aspect, the study of kinetics has proved that the oxidative addition of methyl iodide to the [Rh(CO)2l2] is the rate-determining step of the catalytic cycle. It was also observed that acetyl iodide readily adds to [Rh(CO)2l2], indicating that the acetyl iodide must be scavenged by hydrolysis in order to drive the overall catalytic reaction forward. An alternative to sequential reductive elimination and the hydrolysis of acetyl iodide is the nucleophilic attack of water on the Rh acetyl complex and the production of acetic acid. The relative importance of these two alternative pathways has not yet been fully determined, although the catalytic mechanism is normally depicted as proceeding via the reductive elimination of acetyl iodide from the rhodium center. The addition of iodide salts, especially lithium iodide, can realize the reaction run at lower water concentrations thus, byproduct formation via the water gas shift reaction is reduced, subsequently improving raw materials consumption and reducing downstream separation. In addition to the experimental studies of the catalytic mechanism, theoretical studies have also been carried out to understand the reaction mechanism [17-20]. 

An extensive collection of both experimental and theoretical evidence suggests that the most accurate description of the ylide is one in which an easily pyramidalized carbanion is stabilized by an adjacent tetrahedral phosphonium center (25-34). These conclusions are supported by NMR studies and X-ray crystal structure determinations. Thus, increased electron density at the a-carbon of nonstabilized ylides is consistent with the upheld chemical shift in the NMR spectrum by comparison with the parent phosphonium salts (Table 3, entries 1-5) (26). However, the chemical shift by itself is not a reliable indicator of ylide structure. This is most clearly seen in some of the conjugated ylides, and also in entry 3, which differs from entry 1 only by the presence of lithium bromide. Both the lithium-free (1) and the lithium-containing ylides (3) have the same chemical shift, but they differ dramatically in the coupling constant. In entry 3,... 

The generation of carbenes by the thermolysis of lithium or sodium salts of tosyl-hydrazones continues to provide interesting chemistry. The selectivity exhibited by 7-bicyclo[2,2,l]hept-2-enylidene (generated from the corresponding tosylhydrazone) is quite the opposite to that expected from theoretical predictions and earlier studies. Addition to 3,3-dimethylbut-l-ene affords the syn-isomer (118) as the major adduct and consequently any carbene-7i interaction resulting in bridge bending cannot of itself dominate the stereoselectivity of addition. Furthermore, the intramolecular insertion products of 2-methylbicyclo[2,2,l]hept-2-en-7-ylidene have been characterized and, from the product ratios, the species behaves as a true carbene. A 3-furyl-... 

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