54750-13-9

Upstream product

• 299-42-3 ephedrine 
• 90-82-4 pseudoephedrine 
• 321-98-2 (1S,2R)-(+)-ephedrine 
• 50-98-6 (-)-ephedrine hydrochloride 
• 50-98-6 ephedrine hydrochloride 

Downstream Products

• 130854-68-1 (2R,4R,5S)-3,4-Dimethyl-2-(4-methoxyphenoxy)-5-phenyl-1,3,2-oxazaphospholidine 2-oxide 
• 195433-96-6 (E)-2-((2S,4S,5S)-3,4-Dimethyl-2-oxo-5-phenyl-2λ⁵-[1,3,2]oxazaphospholidin-2-yloxy)-pent-3-enenitrile 
• 54712-22-0 (4S)-3,4r-dimethyl-2-phenoxy-5c-phenyl-[1,3,2]oxazaphospholidine 2c-oxide 
• 54676-65-2 (4S)-2-methoxy-3,4r-dimethyl-5c-phenyl-[1,3,2]oxazaphospholidine 2c-oxide 
• 195434-00-5 (E)-(R)-2-((2S,4S,5S)-3,4-Dimethyl-2-oxo-5-phenyl-2λ⁵-[1,3,2]oxazaphospholidin-2-yloxy)-2-((E)-3-phenyl-allyl)-pent-3-enenitrile 
• 195434-04-9 (S)-2-Benzyl-2-((2S,4S,5S)-3,4-dimethyl-2-oxo-5-phenyl-2λ⁵-[1,3,2]oxazaphospholidin-2-yloxy)-pentanenitrile 
• 195433-99-9 (E)-(R)-2-Benzyl-2-((2S,4S,5S)-3,4-dimethyl-2-oxo-5-phenyl-2λ⁵-[1,3,2]oxazaphospholidin-2-yloxy)-pent-3-enenitrile 
• 195434-01-6 (E)-(R)-2-Allyl-2-((2S,4S,5S)-3,4-dimethyl-2-oxo-5-phenyl-2λ⁵-[1,3,2]oxazaphospholidin-2-yloxy)-pent-3-enenitrile 
• 195434-03-8 (R)-2-((2S,4S,5S)-3,4-Dimethyl-2-oxo-5-phenyl-2λ⁵-[1,3,2]oxazaphospholidin-2-yloxy)-2-ethyl-pentanenitrile 
• 195433-98-8 (E)-(R)-2-((2S,4S,5S)-3,4-Dimethyl-2-oxo-5-phenyl-2λ⁵-[1,3,2]oxazaphospholidin-2-yloxy)-2-ethyl-pent-3-enenitrile 

Relevant academic research and scientific papers

Preparation of chiral phosphorus(V) reagents and their uses with borane in the enantioselective reduction of ketones

Chiral pentavalent phosphorus reagents 5-17 were prepared from POCl3 and ephedrine (or the related α-amino alcohols), followed by substitution with nucleophiles of phenylmagnesium bromide, alcohols, amines, diamines and triamines. The substitution reactions occurred in a stereospecific manner with retention of the configuration at the phosphorus center. The structures of these phosphorus(V) reagents were determined by spectral methods and verified by X-ray diffraction in several instances. These phosphorus(V) reagents were used with borane/dimethylsulfide complex in the enantioselective reduction of aromatic, aliphatic and heterocyclic ketones. The phosphorus(V) reagents likely functioned as Lewis bases to react with borane, forming in situ zwitterionic species as the chiral reducing agents. The reactions were generally carried out at 0 °C in tetrahydrofuran solution with a molar ratio of ketone/borane/phosphoramidate = 1:1:0.2 to afford secondary alcohols with modest enantioselectivity, up to 67% ee in the reduction of 4′-methylacetophenone.

Ein chirales Cyanhydrinphosphat als umgepolte Carbonylverbindung - stereoselektive Synthese von tertiaeren Cyanhydrinen

Stichworte: Asymmetrische Synthesen * Cyanhydrine * Umpolung * Wirkstoffsynthesen

Monitoring Site-Specific Natural Hydrogen Isotope Fractionation Using a Novel Phosphorus-Containing Chiral Discriminating Reagent

The synthesis of a novel chiral discriminating reagent, the ester resulting from the reaction of L-menthylphenylphosphoryl chloride with ethanol, is reported.This reagent, C, is aimed to differentiate the R and S monodeuterated enantiomers of ethanol, which constitutes an important isotopic probe for mechanistic studies and origin inference of natural products.The proportions of the two P-epimeric structures, CA and CB, which compose reagent C are directly accessible by 31P NMR.Analysis of 1D and 2D NMR spectra and theoretical simulations enable the 1H and 13C chemical shifts of CA and CB to be determined.The chemical shift differences exhibited by the methylenic hydrogens of the ethoxy moiety in CA and CB are of the order of 0.3 ppm.These large differences can be mainly attributed to ring current effects.Such effects have been estimated using two different methods on the basis of model conformations of the two epimers, CA and CB, deduced from energy minimization in a quantum mechanical approach.The relative signs of the chemical shift differences δR(C)-δS(C) associated with the pro-R and pro-S positions in the CA and CB isomers cannot be determined from the proton spectrum.The ring current calculations suggest that δR(C)-δS(C) are of opposite signs in the two P-epimers.This interpretation, and consequently the conformational analysis, are supported by the 2H NMR study of a chiral discriminating ester prepared from ethanol selectively enriched in deuterium in the pro-R position by stereospecific exchange reactions involving the enzymatic pair alcohol dehydrogenase-diaphorase.The chiral discriminating reagent, C, was then used for determining the enantiomeric imbalance in ethanol samples obtained from biosynthesis under different conditions, and site-specific fractionation factors were calculated.Key Words: Ethanol Deuterium SNIF-NMR 1H NMR 13C NMR 31P NMR 2D NMR Chiral discrimination Aromatic ring current Molecular structure MOPAC

The Stereochemistry of the Aryl Phosphate/Aryl Phosphonate Rearrangement in 1,3,2-Oxazaphospholidine 2-Oxides

On treatment with LDA/THF (aryloxy)phospholidines in the pseudoephedrine/ephedrine series undergo P-O to P-C rearrangement to afford arylphospholidines with retention of configuration at phosphorus.The stereochemistry of each product was assigned by 1H NM

Note on Carbonyl Derivatives with a Chiral Phosphorylhydrazine

Hydrazones of chiral and achiral ketones with enantiomerically pure phosphorylhydrazine 4 are prepared and analysed by 31P NMR spectroscopy and HPLC for their diastereomeric purity. - Keywords: (2S,4S,5R)-3,4-Dimethyl-2-hydrazido-5-phenyl-1,3,2-oxazaphosp