76411-89-7

Upstream product

• 119-43-7 ethyl 2-phenylbutanoate 
• 90-27-7 2-Phenylbutyric acid 
• 100-58-3 phenylmagnesium bromide 
• 533-68-6 2-bromobutyric acid ethyl ester 
• 60577-21-1 ethyl α-bromo-α-phenylbutyrate 
• 769-68-6 2-phenylbutanenitrile 
• 64-17-5 ethanol 
• 4286-15-1 (S)-2-phenylbutyric acid 

Relevant academic research and scientific papers

The quest for single-enantiomer outcomes in free-radical chemistry

A significant challenge facing free-radical chemists is in the area of stereocontrol, specifically the ability to control the direction of reagent attack at a prochiral radical. While significant inroads have been made in the area of diastereoselective ra

Enantioselective Hydrogen Atom Transfer: Discovery of Catalytic Promiscuity in Flavin-Dependent 'Ene'-Reductases

Flavin has long been known to function as a single electron reductant in biological settings, but this reactivity has rarely been observed with flavoproteins used in organic synthesis. Here we describe the discovery of an enantioselective radical dehalogenation pathway for α-bromoesters using flavin-dependent 'ene'-reductases. Mechanistic experiments support the role of flavin hydroquinone as a single electron reductant, flavin semiquinone as the hydrogen atom source, and the enzyme as the source of chirality.

Cobalt-bisoxazoline-catalyzed asymmetric kumada cross-coupling of racemic α-bromo esters with aryl grignard reagents

The first cobalt-catalyzed asymmetric Kumada cross-coupling with high enantioselectivity has been developed. The reaction affords a unique strategy for the enantioselective arylation of α-bromo esters catalyzed by a cobalt-bisoxazoline complex. A variety of chiral α-arylalkanoic esters were prepared in excellent enantioselectivity and yield (up to 97% ee and 96% yield). The arylated products were transformed into α-arylcarboxylic acids and primary alcohols without erosion of ee. The new enantioenriched α-arylpropionic esters synthesized herein are potentially useful in the development of nonsteroidal anti-inflammatory drugs. This method was conducted on gram-scale and applied to the synthesis of highly enantioenriched (S)-fenoprofen and (S)-ar-turmerone.

CHIRAL ORGANOSILICON HYDRIDES

The invention provides a method for enantioselectively reducing a prochiral carbon centred radical having one or more electron donor groups attached directly to the central prochiral carbon atom of the radical, and/or attached to a carbon atom within 1 to 4 atoms of the central prochiral carbon atom, comprising treating said radical with an activated chiral non-racemic organosilicon hydride in the presence of a Lewis acid. The invention also provides a novel class of activated chiral non-racemic organosilicon hydrides.

ENANTIOSELECTIVE REDUCTION METHOD

The invention provides a method for enantioselectively reducing a prochiral carbon centred radical having one or more electron donor groups attached directly to the central prochiral carbon atom of the radical, and/or attached to a carbon atom within 1 to 4 atoms of the central prochiral carbon atom of the radical, said method comprising generating said radical from a radical precursor compound and reacting said radical with a chiral non-racemic organotin hydride in the presence of a Lewis acid and a co-reducing agent, wherein said co-reducing agent is capable of regenerating chiral non-racemic organotin hydride without substantially reducing said radical or said radical precursor compound.

METHOD OF REMOVING ORGANOTIN RESIDUE

The invention provides a method of separating soluble organotin residue from a reduced product of a reduction reaction that uses an organotin hydride as a reducing agent, the method comprising: (i) contacting a reaction medium comprising said reduced product and soluble organotin residue with a substrate which, (a) is substantially insoluble in the reaction medium, (b) binds at least a portion of said soluble organotin residue, and (c) does not substantially bind the reduced product; (ii) separating said substrate from the reaction medium, thereby removing said at least a portion of organotin residue from the reaction medium; andrecovering the reaction medium comprising the reduced product. The invention also provides a method of performing a reduction reaction using an organotin hydride as a reducing agent that incorporates the method of separating soluble organotin residue.

Single enantiomer free-radical chemistry - Lewis acid-mediated reductions of racemic halides using chiral non-racemic stannanes

Additions of one to two equivalents of Lewis acids that include magnesium salts to free-radical reduction reactions involving ester functionalized radicals and (1R,2S,5R)-menthyldiphenyltin hydride 4, bis((1R,2S,5R)-menthyl) phenyltin hydride 5, tris((1R,

Enantioselective hydrolysis of various racemic α-substituted arylacetonitriles using Rhodococcus sp. CGMCC 0497

The enantioselective hydrolysis of 17 racemic α-substituted arylacetonitriles by Rhodococcus sp. CGMCC 0497 is described. The corresponding (R)-amides and (S)-acids were obtained with excellent enantiomeric excess in most cases. The effect of steric and electronic factors on the outcome of the reactions are discussed here. The results prove that nitrile-converting enzymes are efficient tools for the synthesis of sterically unencumbered chiral α-arylpropionic acids and amides.

Remarkable Lewis acid mediated enhancement of enantioselectivity during free-radical reductions by simple chiral non-racemic stannanes

Additions of 1 equiv, of achiral and chiral Lewis acids to free-radical reduction reactions involving (1S,2S,5R)-menthyldiphenyltin hydride 1, bis[(1S,2S,5R)-menthyl]phenyltin hydride 2, bis[1S,2S,5R)-menthyl][8-(N,N-dimethylamino)naphthyl]tin hydride 3, bis[(1R,2S,5R-menthyl] {1-(S)-N,N-dimethylaminoethyl]phenyl}tin hydride 4 or 3α-dimethylstannyl-5α-cholestane 5 result in remarkable increases in enantioselectivity.