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Paul G. Williard - One of the best experts on this subject based on the ideXlab platform.
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Aggregation and Solvation of n-Butyllithium
Organic letters, 2017Co-Authors: Onkei Tai, Russell Hopson, Paul G. WilliardAbstract:Solution characterizations and ligand binding constants were determined for n-Butyllithium in hydrocarbon and ethereal solvents using diffusion-ordered NMR. In hydrocarbon solvents, n-Butyllithium exists primarily as an octamer at −40 °C and deaggregates to a hexamer when the temperature is increased. In the presence of THF or diethyl ether, n-Butyllithium exists predominantly as a tetra-solvated tetramer and deaggregates to a tetra-solvated dimer in the presence of a large excess or neat THF. The ligand binding constants for the tetra-solvated tetramers were measured using 1H NMR/DOSY titration.
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Aggregation and Solvation of n‑Butyllithium
2017Co-Authors: Onkei Tai, Russell Hopson, Paul G. WilliardAbstract:Solution characterizations and ligand binding constants were determined for n-Butyllithium in hydrocarbon and ethereal solvents using diffusion-ordered NMR. In hydrocarbon solvents, n-Butyllithium exists primarily as an octamer at −40 °C and deaggregates to a hexamer when the temperature is increased. In the presence of THF or diethyl ether, n-Butyllithium exists predominantly as a tetra-solvated tetramer and deaggregates to a tetra-solvated dimer in the presence of a large excess or neat THF. The ligand binding constants for the tetra-solvated tetramers were measured using 1H NMR/DOSY titration
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characterization of hexameric and octameric sec Butyllithium sec butoxide mixed aggregates
European Journal of Inorganic Chemistry, 2013Co-Authors: Russell Hopson, Paul G. WilliardAbstract:Solution-state characterization of sec-Butyllithium in [D8]toluene was conducted by utilizing a variety of NMR spectroscopic experiments including diffusion-ordered NMR spectroscopy (DOSY) with diffusion-coefficient–formula-weight correlation analyses and other one- and two-dimensional NMR spectroscopic techniques. These results suggest that sec-Butyllithium exists primarily as a tetramer/hexamer mixture in hydrocarbon solvents. However, the presence of roughly 2–5 % (by mol ratio) lithium sec-butoxide in both commercially available and laboratory-synthesized sec-Butyllithium solutions due to the reaction with adventitious dioxygen will lead to the formation of a 1:5 sec-butoxide/sec-Butyllithium mixed hexamer. A sec-butoxide/sec-Butyllithium mixed octamer will emerge when the proportion of butoxide to Butyllithium increases.
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Characterization of Hexameric and Octameric sec‐Butyllithium/sec‐Butoxide Mixed Aggregates
European Journal of Inorganic Chemistry, 2013Co-Authors: Russell Hopson, Paul G. WilliardAbstract:Solution-state characterization of sec-Butyllithium in [D8]toluene was conducted by utilizing a variety of NMR spectroscopic experiments including diffusion-ordered NMR spectroscopy (DOSY) with diffusion-coefficient–formula-weight correlation analyses and other one- and two-dimensional NMR spectroscopic techniques. These results suggest that sec-Butyllithium exists primarily as a tetramer/hexamer mixture in hydrocarbon solvents. However, the presence of roughly 2–5 % (by mol ratio) lithium sec-butoxide in both commercially available and laboratory-synthesized sec-Butyllithium solutions due to the reaction with adventitious dioxygen will lead to the formation of a 1:5 sec-butoxide/sec-Butyllithium mixed hexamer. A sec-butoxide/sec-Butyllithium mixed octamer will emerge when the proportion of butoxide to Butyllithium increases.
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Solid-state structures of n-Butyllithium-TMEDA, -THF, and -DME complexes
Journal of the American Chemical Society, 1993Co-Authors: Michael A. Nichols, Paul G. WilliardAbstract:Solid-state structures for a series of n-Butyllithium (n-BuLi)-N,N,N',N'-tetramethylethylenediamine (TMEDA), n-Butyllithium-THF, and n-Butyllithium-dimethoxyethane (DME) complexes and their relevance to previous solution studies of related alkyllithium complexes and synthetic organic chemistry will be presented. X-ray crystal structures for the following complexes have been determined: [(n-BuLi) 4 .TMEDA] ∞ (2); (n-BuLi.TMEDA) 2 (2); (n-BuLi-THF) 4 .n-Hex (3); and [(n-BuLi).DME] ∞ (4). An easy method of purification for n-Butyllithium will also be discussed
Russell Hopson - One of the best experts on this subject based on the ideXlab platform.
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Aggregation and Solvation of n-Butyllithium
Organic letters, 2017Co-Authors: Onkei Tai, Russell Hopson, Paul G. WilliardAbstract:Solution characterizations and ligand binding constants were determined for n-Butyllithium in hydrocarbon and ethereal solvents using diffusion-ordered NMR. In hydrocarbon solvents, n-Butyllithium exists primarily as an octamer at −40 °C and deaggregates to a hexamer when the temperature is increased. In the presence of THF or diethyl ether, n-Butyllithium exists predominantly as a tetra-solvated tetramer and deaggregates to a tetra-solvated dimer in the presence of a large excess or neat THF. The ligand binding constants for the tetra-solvated tetramers were measured using 1H NMR/DOSY titration.
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Aggregation and Solvation of n‑Butyllithium
2017Co-Authors: Onkei Tai, Russell Hopson, Paul G. WilliardAbstract:Solution characterizations and ligand binding constants were determined for n-Butyllithium in hydrocarbon and ethereal solvents using diffusion-ordered NMR. In hydrocarbon solvents, n-Butyllithium exists primarily as an octamer at −40 °C and deaggregates to a hexamer when the temperature is increased. In the presence of THF or diethyl ether, n-Butyllithium exists predominantly as a tetra-solvated tetramer and deaggregates to a tetra-solvated dimer in the presence of a large excess or neat THF. The ligand binding constants for the tetra-solvated tetramers were measured using 1H NMR/DOSY titration
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characterization of hexameric and octameric sec Butyllithium sec butoxide mixed aggregates
European Journal of Inorganic Chemistry, 2013Co-Authors: Russell Hopson, Paul G. WilliardAbstract:Solution-state characterization of sec-Butyllithium in [D8]toluene was conducted by utilizing a variety of NMR spectroscopic experiments including diffusion-ordered NMR spectroscopy (DOSY) with diffusion-coefficient–formula-weight correlation analyses and other one- and two-dimensional NMR spectroscopic techniques. These results suggest that sec-Butyllithium exists primarily as a tetramer/hexamer mixture in hydrocarbon solvents. However, the presence of roughly 2–5 % (by mol ratio) lithium sec-butoxide in both commercially available and laboratory-synthesized sec-Butyllithium solutions due to the reaction with adventitious dioxygen will lead to the formation of a 1:5 sec-butoxide/sec-Butyllithium mixed hexamer. A sec-butoxide/sec-Butyllithium mixed octamer will emerge when the proportion of butoxide to Butyllithium increases.
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Characterization of Hexameric and Octameric sec‐Butyllithium/sec‐Butoxide Mixed Aggregates
European Journal of Inorganic Chemistry, 2013Co-Authors: Russell Hopson, Paul G. WilliardAbstract:Solution-state characterization of sec-Butyllithium in [D8]toluene was conducted by utilizing a variety of NMR spectroscopic experiments including diffusion-ordered NMR spectroscopy (DOSY) with diffusion-coefficient–formula-weight correlation analyses and other one- and two-dimensional NMR spectroscopic techniques. These results suggest that sec-Butyllithium exists primarily as a tetramer/hexamer mixture in hydrocarbon solvents. However, the presence of roughly 2–5 % (by mol ratio) lithium sec-butoxide in both commercially available and laboratory-synthesized sec-Butyllithium solutions due to the reaction with adventitious dioxygen will lead to the formation of a 1:5 sec-butoxide/sec-Butyllithium mixed hexamer. A sec-butoxide/sec-Butyllithium mixed octamer will emerge when the proportion of butoxide to Butyllithium increases.
Omar Farooq - One of the best experts on this subject based on the ideXlab platform.
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Ring tert-Butylation of Benzophenones and Benzaldehyde with tert-Butyllithium and Thionyl Chloride
Synthesis, 1991Co-Authors: George A. Olah, Omar FarooqAbstract:One-flask ring tert-butylation of benzophenones and benzaldehyde with tert-Butyllithium and thionyl chloride is reported. The scope of the reaction and the suggested mechanism are discussed.
Jorge Berriel - One of the best experts on this subject based on the ideXlab platform.
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Vinyllithiums from butyl-vinyl tellurides and bis-vinyl tellurides
Tetrahedron Letters, 2001Co-Authors: Simone M. G. De Barros, João V. Comasseto, Jorge BerrielAbstract:Abstract Butyl vinyl tellurides and bis-vinyl tellurides furnish vinyllithiums with retention of configuration in good yields upon treatment with n-Butyllithium at −78°C.
Ekkehard Fluck - One of the best experts on this subject based on the ideXlab platform.
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Neue Carbodiphosphorane. Notiz zur Reaktion zwischen Bis(dimethylamino)fluormethylidenphosphoran und n-Butyllithium / New Carbodiphosphoranes. Note on the Reaction between Bis(dimethylamino)fluoromethylidene-phosphorane and n-Butyllithium
Zeitschrift für Naturforschung B, 1992Co-Authors: W. Plass, M. Spahn, Gernot Heckmann, Ekkehard FluckAbstract:The main product from the reaction between bis(dimethylamino)fluoromethylidene-phosphorane (1) and n-Butyllithium in the presence of tetramethylethylenediamine is n-butyl-dimethylamino-methyl-{[tris(dimethylamino)phosphoranylidene]methylene}-phosphorane (7). As a by-product from the reaction between methyl-bis(dimethylamino)difluorophosphorane and n-Butyllithium bis(dimethylamino)-methyl-{[n-butyl-bis(dimethylamino)phosphoranylidene]methylene}-phosphorane (9) was isolated in small yield. The new carbodiphosphoranes 7 and 9 are characterized by their ¹H, ¹³C, and ³¹P NMR and mass spectra.
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Neue Carbodiphosphorane. Notiz zur Reaktion zwischen Bis(dimethylamino)fluormethylidenphosphoran und n-Butyllithium
Zeitschrift für Naturforschung. B A journal of chemical sciences, 1992Co-Authors: W. Plass, M. Spahn, Gernot Heckmann, Ekkehard FluckAbstract:The main product from the reaction between bis(dimethylamino)fluoromethylidene-phosphorane (1) and n-Butyllithium in the presence of tetramethylethylenediamine is n-butyl-dimethylamino-methyl-{[tris(dimethylamino)phosphoranylidene]methylene}-phosphorane (7). As a by-product from the reaction between methyl-bis(dimethylamino)difluorophosphorane and n-Butyllithium bis(dimethylamino)-methyl-{[n-butyl-bis(dimethylamino)phosphoranylidene]methylene}-phosphorane (9) was isolated in small yield
