191480-65-6Relevant academic research and scientific papers
An Aluminum Fluoride Complex with an Appended Ammonium Salt as an Exceptionally Active Cooperative Catalyst for the Asymmetric Carboxycyanation of Aldehydes
Brodbeck, Daniel,Broghammer, Florian,Meisner, Jan,Klepp, Julian,Garnier, Delphine,Frey, Wolfgang,K?stner, Johannes,Peters, René
, p. 4056 - 4060 (2017)
Al?F bonds are among the most stable σ bonds known, exhibiting an even higher bond energy than Si?F bonds. Despite a stability advantage and a potentially high Lewis acidity of Al?F complexes, they have not been described as structurally defined catalysts
Asymmetric Carboxycyanation of Aldehydes by Cooperative AlF/Onium Salt Catalysts: from Cyanoformate to KCN as Cyanide Source
Brodbeck, Daniel,álvarez-Barcia, Sonia,Meisner, Jan,Broghammer, Florian,Klepp, Julian,Garnier, Delphine,Frey, Wolfgang,K?stner, Johannes,Peters, René
supporting information, p. 1515 - 1524 (2019/01/09)
Asymmetric 1,2-additions of cyanide yield enantioenriched cyanohydrins as versatile chiral building blocks. Next to HCN, volatile organic cyanide sources are usually used. Among them, cyanoformates are more attractive on technical scale than TMSCN for cos
Asymmetric Grignard Synthesis of Tertiary Alcohols through Rational Ligand Design
Bieszczad, Bartosz,Gilheany, Declan G.
supporting information, p. 4272 - 4276 (2017/04/03)
A simple, general and practical method is reported for highly enantioselective construction of tertiary alcohols through the direct addition of organomagnesium reagents to ketones. Discovered by rational ligand design based on a mechanistic hypothesis, it has an unprecedented broad scope. It utilizes a new type of chiral tridentate diamine/phenol ligand that is easily removed from the reaction mixture. It is exemplified by application to a formal asymmetric synthesis (>95:5 d.r.) of vitamin E.
Enantioselective reduction of α-substituted ketones mediated by the boronate ester TarB-NO2
Eagon, Scott,Ball-Jones, Nicholas,Haddenham, Dustin,Saavedra, Jaime,Delieto, Cassandra,Buckman, Matthew,Singaram, Bakthan
supporting information; experimental part, p. 6418 - 6421 (2010/12/30)
A facile and mild reduction procedure is reported for the preparation of chiral secondary alcohols prepared from α-substituted ketones using sodium borohydride and the chiral boronate ester (l)-TarB-NO2. Direct reduction of substituted ketones bearing Lewis basic heteroatoms generally provided secondary alcohols of only modest enantiomeric excess likely due to either competition between the target carbonyl and the functionalized sidechains at the Lewis acidic boron atom in TarB-NO2 or the added steric bulk of the α-sidechain. As an alternative method, these substrates were synthesized using TarB-NO2 via a two-step procedure involving the reduction of an α-halo ketone to a chiral terminal epoxide, followed by regioselective/regiospecific epoxide opening by various nucleophiles. This procedure provides access to a variety of functionalized secondary alcohols including β-hydroxy ethers, thioethers, nitriles, and amines with enantiomeric excesses of 94% and yields up to 98%.
ISOSELECTIVE POLYMERIZATION OF EPOXIDES
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Page/Page column 63; 64, (2009/04/25)
The present invention provides novel bimetallic complexes and methods of using the same in the isoselective polymerization of epoxides. The invention also provides methods of kinetic resolution of epoxides. The invention further provides polyethers with high enantiomeric excess that are useful in applications ranging from consumer goods to materials.
