172534-72-4

Upstream product

• 132161-97-8 (S)-N-(1-Cyano-3-phenylpropan-2-yl)-4-methylbenzenesulfonamide 
• 64-19-7 acetic acid 
• 3182-95-4 L-Phenylalaninol 
• 98-59-9 p-toluenesulfonyl chloride 
• 124-38-9 carbon dioxide 
• 71535-50-7 (S)-(+)-2-benzyl-1-(p-tolylsulfonyl)aziridine 
• 10119-00-3 tosyl-L-phenylalanyl diazomethane 
• 90365-18-7 N-(p-toluenesulfonyl)-L-phenylalanyl chloride 
• 13505-32-3 N-tosyl-(S)-phenylalanine 
• 221468-33-3 (S)-N-[1-(iodomethyl)-2-phenylethyl]-4-methyllbenzenesulfonamide 
• 82495-70-3 (2S)-2-p-toluenesulfonamido-3-phenylpropanol 
• 63-91-2 L-phenylalanine 
• 209850-63-5 (S)-4-Phenyl-3-(toluene-4-sulfonylamino)-butyric acid methyl ester 
• 154047-41-3 (S)-1-(2-trimethylsilyl-1,3-dithian-2-yl)-2-(4-methylbenzenesulfonamido)-3-phenylpropane 

Downstream Products

• 209850-57-7 N-((S)-1-Benzyl-4-diazo-3-oxo-butyl)-4-methyl-benzenesulfonamide 
• 221467-77-2 (S)-(4-phenyl-3-tosylamidobutanoyl)dimethylphenylsilane 
• 936012-10-1 N-(1-benzyl-3-hydroxy-propyl)-4-methyl-benzenesulfonamide 
• 221468-44-6 (S)-4-phenyl-3-tosylamidobutanoyl chloride 

Relevant academic research and scientific papers

Ni-Catalyzed Carboxylation of Aziridines en Route to β-Amino Acids

A Ni-catalyzed reductive carboxylation of N-substituted aziridines with CO2 at atmospheric pressure is disclosed. The protocol is characterized by its mild conditions, experimental ease, and exquisite chemo- and regioselectivity pattern, thus unlocking a new catalytic blueprint to access β-amino acids, important building blocks with considerable potential as peptidomimetics.

Substituted 1,4-benzoxazepines, 1,5-benzoxazocines, and N- and S-variants

"Chemical Equation Presented" Nucleophilic cleavage of enantiomerically pure 1,2-cyclic sulfamidates with phenol, aniline, and thiophenol nucleophiles, followed by a Mitsunobu reaction, including use of a o-quinomethide variant of this process, provides a

Stereoselective synthesis of 2,4,5-trisubstituted piperidines by carbonyl ene and Prins cyclisations

An approach to 2,4,5-trisubstituted piperidines is reported, in which the key step is the Prins or carbonyl ene cyclisation of aldehydes of the type 1. Prins cyclisation catalysed by concentrated hydrochloric acid in CH 2Cl2 at -78 °C afforded good yields of two of the four possible diastereomeric piperidines, with the 4,5-cis product 7 predominating in a diastereomeric ratio of up to 94: 6. The diastereoselectivity of the cyclisation decreased as the 2-substituent increased in size, becoming unselective for very bulky 2-substituents. In contrast, cyclisation catalysed by MeAlCl2 in CH2Cl2 or CHCl3 at temperatures of between 20-60 °C, favoured the 4,5-trans diastereomer 8, in a diastereomeric ratio of up to 99: 1. The low-temperature cyclisations catalysed by HCl proceed under kinetic control via a mechanism involving the development of significant carbocationic character, in which the 4,5-cis cation is more stable than the 4,5-trans cation as a result of overlap with the neighbouring oxygen. The cyclisations catalysed by MeAlCl2 proceed under thermodynamic control, affording the product in which both the 4- and 5-substituents are equatorial.

A convenient synthetic route to enantiopure N-tosylazetidines from α-amino acids

A general and convenient synthetic route to various chiral 2-substituted- and 2,4-disubstituted-N-tosylazetidines (ee >99%) is described in good overall yields starting from chiral α-amino acids using very simple chemistry.

Synthesis of enantiopure β- and γ-amino alcohols from homochiral α- and β-aminoacylsilanes as stable synthetic equivalents of α- and β-amino aldehydes

A practical route is described for the synthesis of enantiopure β- and γ-amino alcohols with two stereocenters, starting from homochiral α- (1 and 5) and β- (13 and 16) -aminoacylsilanes, and involving stereoselective addition of allylmetal compounds and subsequent stereospecific protiodesilylation of the adducts. The degree of diastereoselectivity achieved in the nucleophilic addition step depends on both the nitrogen- protecting group and the reagents used. Diastereomeric excess (de) values equal to or higher than 98% were obtained in the TiCl4-promoted allylation of the N-Pht aminoacylsilanes 1 and 13 and of the N-Ts-aminoacylsilane 5 with allyltrimethylsilane. Lower de values were obtained in the Sc(OTf)3- catalyzed anylation of 5 with tetraallyltin and in the additions of both allyltrimethylsilane and tetraallyltin to the N-Ts-β-aminoacylsilane 16. Protiodesilylation of the adducts, leading to the β- and γ-amino alcohols, was accomplished with TBAF, except in the case of the adducts obtained from 5. For these, a preliminary removal of the tosyl group was necessary, which was accomplished with simultaneous desilylation by treatment with Na in liquid ammonia.

Wolff rearrangement of diazo ketones derived from N-p-tolylsulfonyl-protected α- and β-amino acids

Diazo ketones derived from N-p-tolylsulfonyl (tosyl)-protected α- and β-amino acids have been synthesized and their diazo decomposition under standard Wolff rearrangement conditions, PhCO2Ag-Et3N-MeOH, has been investigated. It is observed that, under these conditions, several different reaction pathways, including direct carbene N-H insertion, are possible. The reaction is markedly affected by the N-protecting group, the substrate structure and solvent. For those diazo ketones derived from N-tosyl-protected β-amino acids, the diazo decomposition with anhydrous THF as solvent and PhCO2Ag dissolved in Et3N as catalyst gives the corresponding 5-substituted pyrrolidinones in excellent yields.

Ring-opening of N-tosyl aziridines by 2-lithiodithianes

The reaction of lithiated dithianes 6-8 and 15 and 16 with enantiopure N-sulfonylated aziridines 1 and 2 leads via regiospecific nucleophilic ring-opening to enentiopure N-tosyl 2-(2'-dithianyl) secondary amines in good to excellent yields.These compounds