53432-39-6

Upstream product

• 2902-69-4 2,2,2-trichloroacetophenone 
• 67-56-1 methanol 
• 1391854-02-6 (R)-1-phenyl-2,2,2-trichloroethyl (R)-1-(4-bromophenyl)ethylcarbamate 
• 100-52-7 benzaldehyde 
• 2000-43-3 2,2,2-trichloro-1-phenylethanol 

Downstream Products

• 56751-12-3 2-chloro-1-phenylethanol 
• 29289-35-8 2-azido-2-phenylacetic acid 
• 29129-67-7 (S)-2-azido-2-phenylacetic acid 
• 29125-25-5 (R)-2-azido-2-phenylacetic acid 
• 1335126-62-9 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(2,4-dichlorophenyl)aziridine-1-carboxylate 
• 1335126-63-0 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(4-fluoro-2-methylphenyl)aziridine-1-carboxylate 
• 1335126-64-1 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(2-bromo-4-methylphenyl)aziridine-1-carboxylate 
• 1335126-65-2 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(2,5-dichlorophenyl)aziridine-1-carboxylate 
• 1335126-66-3 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(5-chloro-2-nitrophenyl)aziridine-1-carboxylate 
• 1335126-67-4 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(2,3-dichlorophenyl)aziridine-1-carboxylate 
• 1335126-68-5 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(3,4-dichlorophenyl)aziridine-1-carboxylate 
• 1335126-69-6 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(4-bromo-3-nitrophenyl)aziridine-1-carboxylate 
• 1335126-70-9 (R)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(3-bromophenyl)aziridine-1-carboxylate 
• 1374003-41-4 (S)-((R)-1-phenyl-2,2,2-trichloroethyl) 2-(3-bromophenyl)aziridine-1-carboxylate 

Relevant academic research and scientific papers

London Dispersion Interactions Rather than Steric Hindrance Determine the Enantioselectivity of the Corey–Bakshi–Shibata Reduction

The well-known Corey–Bakshi–Shibata (CBS) reduction is a powerful method for the asymmetric synthesis of alcohols from prochiral ketones, often featuring high yields and excellent selectivities. While steric repulsion has been regarded as the key director of the observed high enantioselectivity for many years, we show that London dispersion (LD) interactions are at least as important for enantiodiscrimination. We exemplify this through a combination of detailed computational and experimental studies for a series of modified CBS catalysts equipped with dispersion energy donors (DEDs) in the catalysts and the substrates. Our results demonstrate that attractive LD interactions between the catalyst and the substrate, rather than steric repulsion, determine the selectivity. As a key outcome of our study, we were able to improve the catalyst design for some challenging CBS reductions.

Trichloromethyl ketones: Asymmetric transfer hydrogenation and subsequent Jocic-type reactions with amines

Amino-amides are important pharmaceutical building-blocks. The enantioselective reduction of trichloromethyl ketones using ruthenium transfer hydrogenation catalysts is reported. The products react in a range of Jocic-type reactions to give enantiomerically enriched amino-amides.

Stereoselective intermolecular C-H amination reactions

A novel chiral N-mesyloxycarbamate to perform rhodium-catalyzed stereoselective C-H amination reactions is reported. Chiral benzylic and propargylic amines are produced in good yields and selectivities using ethyl acetate as solvent. The corresponding free amines are easily obtained by cleavage of the chiral reagent, which could also be recovered. This journal is

Solution-phase synthesis and evaluation of tetraproline chiral stationary phases

A protocol was developed for the solution-phase synthesis of multigram amounts of two 9-fluorenylmethoxycarbonyl (Fmoc)-protected tetraproline peptides. These tetraproline peptides were then attached to amino derivatized silica gel. The replacement of the Fmoc group with the trimethylacetyl group lead to two tetraproline chiral stationary phases (CSPs). A comparison of the chromatographic behavior of these two solution-phase-synthesized tetraproline CSPs with that prepared by stepwise solid-phase synthesis revealed that all three had similar chromatographic performance for resolving 53 model analytes. This suggests that the solution-phase synthesis of oligoprolines, which allows for the specific benefits of good batch reproducibility, selector homogeneity, and possibly low cost, is a feasible alternative to the solid-phase synthesis of oligoproline CSPs. Copyright

Stereoselective rhodium-catalyzed amination of alkenes

The first stereoselective rhodium-catalyzed intermolecular aziridination and C-H amination of alkenes to produce chiral carbamate-protected aziridines and allylic amines is described. Good yields and diastereoselectivities were achieved using a readily av

The influence of fluorine on the asymmetric reduction of fluoromethyl ketones

A comparative study of the asymmetric reduction of representative aryl and alkyl α-fluoro- and α-chloromethyl ketones using (-)-diisopinocampheylchloroborane [(-)-DIP-Chloride] and (-)-B-isopinocampheyl-9-borabicyclo[3.3.1]nonane [R-Alpine-Borane] has been made. It was observed that DIP-Chloride is superior in terms of the rate and enantioselectivity for both classes of halo-ketones. While the reduction of monofluoroacetone and trifluoroacetone with DIP-Chloride provided the product alcohols in 61% ee and 96% ee, respectively, the reduction of difluoroacetone yielded only 5% ee. The influence of a lone halogen atom was not observed for monochloroacetone, all of which point towards a chelating effect of monofluoroacetone on the Lewis acidic chloroborane.

A practical asymmetric synthesis of homochiral α-arylglycines

Enantioselective reduction of a series of substituted aryl trichloromethyl ketones with the CBS-catecholborane reagent afforded homochiral aryl trichloromethyl carbinols which have been elaborated to give homochiral α-arylglycines in high e.e.

Catalytic enantioselective synthesis of secondary alcohols using C2-symmetric diamino diol ligands

A new class of diamino diols was evaluated as catalytic ligands in the enantioselective borane reduction of aromatic ketones and the enantioselective ethylation of arylaldehydes with diethylzinc. By variation of the substitution pattern on the ketone, e.e.s of up to 94% could be obtained by in situ borane reduction using 0.025 equiv. of the ligand at 35°C in THF. N,N,N′,N′-Tetramethyldiamino diol and N,N′-dialkyl diamino diol were used as promoters for the enantioselective addition of diethylzinc reagent to the arylaldehyde, where use of 0.1 equiv. of N,N,N′,N′-tetramethyl diamino diol as catalyst in the addition of diethylzinc to arylaldehyde achieved e.e.s of up to 98%.

A CATALYTIC ENANTIOSELECTIVE SYNTHESIS OF CHIRAL MONOSUBSTITUTED OXIRANES

A new catalytic enentioselective synthesis of monosubstituted oxiranes has been developed from achiral trichloromethyl ketones by (a) enentioselective carbonyl reduction, (b) selective bis-dechlorination and (c) base-induced ring closure of the resulting chlorohydrins.