- Grignard reagent/borohydride combinations alkylation/reduction of esters
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The one step transformation of esters into secondary alcohols (70-80% yields) has been performed with a Grignard reagent in the presence of calcium or zinc borohydride. Under the same conditions, vinylic Grignard reagents gave γ,δ-unsaturated alcohols in good yields through three successive reactions: addition to the ester carbonyl, then conjugate addition and, finally reduction).
- Hallouis, Sophie,Saluzzo, Christine,Amouroux, Roger
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- Synthesis of new chiral aliphatic amino diselenides and their application as catalysts for the enantioselective addition of diethylzinc to aldehydes
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(Matrix presented) A set of chiral aliphatic amino diselenides have been synthesized from readily available starting materials in a straightforward synthetic route via the ring-opening reaction of the parent aziridines. These ligands have been tested as catalysts for the enantioselective addition of diethylzinc to aldehydes. The influence of the alkyl group substituents on the stereoselectivity has been studied, and in the best case, an enantiomeric excess up to 99% could be obtained by using only 0.5 mol % of the chiral diselenide 3a.
- Braga, Antonio L.,Paixao, Marcio W.,Luedtke, Diogo S.,Silveira, Claudio C.,Rodrigues, Oscar E. D.
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- IONIZABLE AMINE LIPIDS AND LIPID NANOPARTICLES
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The disclosure provides ionizable amine lipids and salts thereof (e.g., pharmaceutically acceptable salts thereof) useful for the delivery of biologically active agents, for example delivering biologically active agents to cells to prepare engineered cells. The ionizable amine lipids disclosed herein are useful as ionizable lipids in the formulation of lipid nanoparticle-based compositions.
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Page/Page column 164
(2020/11/04)
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- A manganese-containing molecular sieve catalyst designed for the terminal oxidation of dodecane in air
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MnIII ions that replace a few percent of the framework AlIII sites in a microporous aluminophosphate - number 18, with a pore aperture of 3.8 A - function as catalytically active centres for the selective oxidation of dodecane preferentially at C1 and C2.
- Raja, Robert,Thomas, John Meurig
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p. 1841 - 1842
(2007/10/03)
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- Direct Formation and Reaction of Thienyl-Based Organocopper Reagents
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The preparation of a highly reactive zerovalent copper complex by the direct reduction of lithium (2-thienylcyano)cuprate with preformed lithium naphthalenide is described.This active copper species oxidatively adds to carbon-halogen bonds to form organocopper reagents.The ability to directly form the organocopper reagent from organic halides and active copper allows for the incorporation of a wide variety of functionalities to be present in the organic halides and the organocopper reagents.Significantly, this formulation of active copper was able to oxidatively add to allyl chlorides and acetates at low temperatures to allow the direct formation of allylic organocopper reagents without Wurtz-type homocoupling.These functionalized organocopper compounds are able to undergo a variety of reactions, such as cross-coupling with acid chlorides, 1,4-conjugate addition with α,β-unsaturated carbonyl compounds, and intermolecular and intramolecular epoxide-opening reactions.Subsequently, this copper species avoids the use of phosphine ligands affording the product isolation much more convenient than with phosphine-based organocopper reagents.
- Rieke, Reuben D.,Klein, Walter R.,Wu, Tse-Chong
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p. 2492 - 2500
(2007/10/02)
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- NEW ORGANOCOPPER REAGENTS PREPARED UTILIZING HIGHLY REACTIVE COPPER
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Highly reactive copper solutions have been prepared by the lithium naphthalide reduction of copper(I) iodide/trialkylphosphine complexes.These activated copper solutions will react with organic halides under very mild conditions to form stable organocopper reagents.Significantly, the organocopper reagents can contain considerable functionalities such as ester, nitrile, chloride, epoxide, and ketone groups.These functionalized organocopper species undergo many reactions typical of other organocopper species.Intermolecular 1,4-additions, epoxide-opening reactions, and ketone formation with acid chlorides have been successfully achieved.In addition, this methodology has been applied to an intramolecular epoxide-cleavage reaction.The influence of the connecting chain length, substitution pattern, reaction solvent, and CuI/phosphine complex upon the regioselectivity of the intramolecular cyclization is described.
- Rieke, Reuben D.,Wehmeyer, Richard M.,Wu, Tse-Chong,Ebert, Greg W.
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p. 443 - 454
(2007/10/02)
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- DIRECT FORMATION AND REACTION OF FUNCTIONALIZED THIENYL-BASED ORGANOCOPPER REAGENTS
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Highly reactive copper solutions have been prepared by the direct reduction of lithium 2-thienylcyanocuprate.Product isolation was much easier using the thienyl-based organocopper reagents as opposed to phosphine-based organocopper reagents
- Rieke, Reuben D.,Wu, Tse-Chong,Stinn, Dean E.,Wehmeyer, Richard M.
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p. 1833 - 1840
(2007/10/02)
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- Conversion of alkyl and aryl hydroxy compounds producing aldehyde, alcohol and ketone using manganese oxide/nickel oxide/magnesium oxide catalysts
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Alkyl and aryl hydroxy compounds are converted to aldehydes, alcohols, and ketones in the presence of hydrogen using a catalyst comprised of the oxides of manganese, nickel and magnesium.
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