657408-07-6Relevant articles and documents
Coordination Chemistry of Borane in Solution: Application to a STING Agonist
Lemaire, Sébastien,Zhdanko, Alexander,van der Worp, Boris A.
, (2022/04/09)
Equilibrium constants were determined for ligand exchange reactions of borane complexes with various oxygen, sulfur, nitrogen, and phosphorus nucleophiles in solution, and a binding affinity scale was built spanning a range of 12 orders of magnitude. While the Keq are minimally dependent on the solvent, the rate of ligand exchange varies significantly. The fastest and slowest rates were observed in THF and CDCl3, respectively. Moreover, the ligand exchange rate differs in a very broad range depending on stability of the starting complex. Binding of BH3 was found to be much more sensitive to steric factors than protonation. Comparing nitrogen bases having equal steric properties, a linear correlation of BH3 binding affinity vs. Br?nsted acidity was found. This correlation can be used to quickly estimate the BH3 binding affinity of a substrate if pKa is known. Kinetic studies suggest the ligand exchange to occur as a bimolecular SN2 reaction unless other nucleophilic species were present in the reaction mixture.
Chemoselective Reduction of Phosphine Oxides by 1,3-Diphenyl-Disiloxane
Buonomo, Joseph A.,Eiden, Carter G.,Aldrich, Courtney C.
supporting information, p. 14434 - 14438 (2017/10/23)
Reduction of phosphine oxides to the corresponding phosphines represents the most straightforward method to prepare these valuable reagents. However, existing methods to reduce phosphine oxides suffer from inadequate chemoselectivity due to the strength of the P=O bond and/or poor atom economy. Herein, we report the discovery of the most powerful chemoselective reductant for this transformation to date, 1,3-diphenyl-disiloxane (DPDS). Additive-free DPDS selectively reduces both secondary and tertiary phosphine oxides with retention of configuration even in the presence of aldehyde, nitro, ester, α,β-unsaturated carbonyls, azocarboxylates, and cyano functional groups. Arrhenius analysis indicates that the activation barrier for reduction by DPDS is significantly lower than any previously calculated silane reduction system. Inclusion of a catalytic Br?nsted acid further reduced the activation barrier and led to the first silane-mediated reduction of acyclic phosphine oxides at room temperature.
ORGANIC COMPOUND AND ELECTROCHROMIC DEVICE USING THE SAME
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, (2015/09/22)
The present invention provides an organic compound represented by the following general formula [1], the organic compound having high solubility in a polar solvent used in an EC device, high transparency in the bleached state and high stability against repetition of an oxidation-reduction reaction.
General method for functionalized polyaryl synthesis via aryne intermediates
Truong, Thanh,Mesgar, Milad,Le, Ky Khac Anh,Daugulis, Olafs
, p. 8568 - 8576 (2014/07/07)
A method for base-promoted arylation of arenes and heterocycles by aryl halides and aryl triflates is described. Additionally, in situ electrophilic trapping of ArLi intermediates generated in the reaction of benzyne with deprotonated arenes or heterocycles has been developed, providing rapid and easy access to a wide range of highly functionalized polyaryls. Base-promoted arylation methodology complements transition-metal-catalyzed direct arylation and allows access to structures that are not easily accessible via other direct arylation methods. The reactions are highly functional-group tolerant, with alkene, ether, dimethylamino, trifluoromethyl, ester, cyano, halide, hydroxyl, and silyl functionalities compatible with reaction conditions.
Highly chemoselective Mono-Suzuki arylation reactions on all three dichlorobenzene isomers and applications development
Ullah, Ehsan,McNulty, James,Robertson, Al
, p. 2127 - 2131 (2012/06/01)
A Pd catalyst system is described that allows very high chemoselective monoarylation on all three isomers of dichlorobenzene. Direct application of these commodity chemicals to high-value ligands, anilines, azides, and carbazoles was achieved through this process discovery.
METHYLENE FURANONE DERIVATIVES AND USE OF SAID DERIVATIVES AS A PHOTOPROTECTING OR ANTIOXIDANT OR DEPIGMENTATION AGENT IN COSMETIC OR DERMATOLOGICAL COMPOSITIONS
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Page/Page column 9, (2011/08/06)
The present invention relates to novel methylene furanone derivatives as well as the use thereof as a protective, antioxidant, or depigmentation agent in cosmetic or dermatological compositions. The invention also relates to a method for preparing said derivatives involving a Suzuki-Miyaura coupling reaction from corresponding dibromofuranone derivatives. The invention also relates to a method of preparation involving a coupling reaction of 2-methoxy-furan derivatives with a ketone followed by dehydration.
Polystyrene sulfonyl chloride: A highly orthogonal linker resin for the synthesis of nitrogen-containing heterocycles
Mentel, Matthias,Schmidt, Axel M.,Gorray, Michael,Eilbracht, Peter,Breinbauer, Rolf
supporting information; experimental part, p. 5841 - 5844 (2009/12/08)
One linker, broad application: A simple sulfonamide linker for primary and secondary amines was used for the construction of small libraries of privileged indole and quinolone structures on a solid phase. After the synthesis, the products can be liberated ion a traceless manner under electron transfer conditions or according to a "safety catch" principle.
Catalysts for Suzuki-Miyaura coupling processes: Scope and studies of the effect of ligand structure
Barder, Timothy E.,Walker, Shawn D.,Martinelli, Joseph R.,Buchwald, Stephen L.
, p. 4685 - 4696 (2007/10/03)
Suzuki-Miyaura coupling reactions of aryl and heteroaryl halides with aryl-, heteroaryl- and vinylboronic acids proceed in very good to excellent yield with the use of 2-(2′,6′-dimethoxybiphenyl) dicyclohexylphosphine, SPhos (1). This ligand confers unprecedented activity for these processes, allowing reactions to be performed at low catalyst levels, to prepare extremely hindered biaryls and to be carried out, in general, for reactions of aryl chlorides at room temperature. Additionally, structural studies of various 1·Pd complexes are presented along with computational data that help elucidate the efficacy that 1 imparts on Suzuki-Miyaura coupling processes. Moreover, a comparison of the reactions with 1 and with 2-(2′,4′,6′-triisopropylbiphenyl)diphenylphosphine (2) is presented that is informative in determining the relative importance of ligand bulk and electron-donating ability in the high activity of catalysts derived from ligands of this type. Further, when the aryl bromide becomes too hindered, an interesting C-H bond functionalization-cross-coupling sequence intervenes to provide product in high yield.
