216220-10-9

Upstream product

• 112245-13-3 (S)-tert-leucinol 
• 98-59-9 p-toluenesulfonyl chloride 

Downstream Products

• 875438-80-5 (3R)-(p-toluenesulfonyl)amino-4,4-dimethylpentonitrile 
• 875438-89-4 (3R)-[N-(3-methylbut-2-enyl)-N-(p-toluenesulfonyl)amino]-4,4-dimethylpentanal 
• 875438-84-9 (3R)-[N-(3-methylbut-2-enyl)-N-(p-toluenesulfonyl)amino]-4,4-dimethylpentionitrile 
• 216220-08-5 (S)-N-(p-toluenesulfonyl)-2-tert-butylaziridine 
• 286454-86-2 (S)‐1‐(diphenylphosphino)‐3,3‐dimethylbutan‐2‐amine 
• 602307-06-2 (S)-1-diphenylphosphino-2-(4-methylphenylsulfonylamino)-3,3-dimethylbutane 

Relevant academic research and scientific papers

Cu-Catalyzed [3 + 3] Cycloaddition of Isocyanoacetates with Aziridines and Stereoselective Access to α,γ-Diamino Acids

We report herein an efficient Cu-catalyzed formal [3 + 3] cycloaddition of isocyanoacetates with readily available aziridines of different substitution patterns, which provides a practical access to valuable 1,4,5,6-tetrahydropyrimidine derivatives. In pa

Enantioselective α-Etherification of Branched Aldehydes via an Oxidative Umpolung Strategy

Saturated carbonyl compounds are, via their enolate analogues, inherently nucleophilic at the α-position. In the presence of a benzoquinone oxidant, the polarity of the α-position of racemic α-branched aldehydes is inverted, allowing for an enantioselective etherification using readily available oxygen-based nucleophiles and an amino acid-derived primary amine catalyst. A survey of benzoquinone oxidants identified p-fluoranil and DDQ as suitable reaction partners. p-Fluoranil enables the preparation of α-aryloxylated aldehydes using phenol nucleophiles in up to 91 % ee, following either a one-step or a two-step, one-pot protocol. DDQ allows for a more general etherification protocol in combination with a broader range of alcohol nucleophiles with enantioselectivities up to 95 % ee. Control experiments and isolation of a key quinol intermediate supports a mechanism proceeding via an SN2 dynamic-kinetic resolution. These studies provide the basis for an aminocatalytic umpolung concept that allows for the asymmetric construction of tertiary ethers in the α-position of aldehydes.

Enantioselective copper-catalyzed 1,4-addition of dialkylzincs to enones followed by trapping with allyl iodide derivatives

Enantioselective copper-catalyzed 1,4-addition of dialkylzincs to enones proceeded in the presence of 0.1 mol% of Cu(OTf)2 and 0.25 mol% of an N,N,P-ligand containing a quinoline moiety to afford the corresponding conjugated adducts in 99%ee. The intermediate zinc enolates were trapped with substituted allyl iodides to give disubstituted ketones with high diastereoselectivity and enantioselectivity.

Novel N,N,P-tridentate ligands for the highly enantioselective copper-catalyzed 1,4-addition of dialkylzincs to enones

(Chemical Equation Presented) Use of 0.25 mol % of the N,N,P-tridentate ligand containing the 2-quinolyl moiety (1 and 2) and 0.1 mol % of Cu(OTf) 2 enabled the enantioselective 1,4-addition of dialkylzincs to cyclic enones to produce 1,4-adduc

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.

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

Intramolecular carbonyl ene reactions present a method for ring closure, leading to the formation of two contiguous stereocentres with an often high degree of stereocontrol. The extension of this approach to the synthesis of 2,4,5-trisubstituted piperidin