64754-77-4Relevant academic research and scientific papers
Diastereoselective darzens condensations of α-haloamides: Influence of aryl substituents on diastereoselectivity
North, Michael,Pizzato, Francesca
experimental part, p. 552 - 556 (2010/04/23)
N, N-Diaryl α-haloamides undergo Darzens condensations with aldehydes induced by metal hydroxides. The diastereoselectivity of epoxide formation is strongly influenced by the electronic properties of the arylamide, which can be rationalised on the basis of the acidity of the substrate hydrogens and hence on reaction occurring under kinetic or thermodynamic control.
Diastereoselective Darzens condensations
Achard, Thierry J.R.,Belokon', Yuri N.,Hunt, Jamie,North, Michael,Pizzato, Francesca
, p. 2961 - 2964 (2008/02/04)
N,N-Diphenyl-α-haloacetamides undergo Darzens condensations with aldehydes under heterogeneous reaction conditions in the presence of a metal hydroxide base. By appropriate choice of solvent, base and halide, very high diastereoselectivities favouring for
A stereocontrolled approach to electrophilic epoxides
Meth-Cohn, Otto,Moore, Clive,Taljaard, Heinrich C.
, p. 2663 - 2674 (2007/10/02)
Lithium t-butyl hydroperoxide (easily generated by addition of an alkyl-lithium to anhydrous t-butyl hydroperoxide in THF solution) is a powerful reagent for the epoxidation of electrophilic alkenes at -20 to 0 °C under full stereocontrol. Thus αβ-unsaturated esters, sulphones, sulphoximines, and amides are readily epoxidised with complete regio- and stereo-specificity and with considerable chiroselectivity (20-100%) when appropriate chiral auxiliaries such as menthyl, 8-phenylmenthyl, or a camphor-sulphonamide derivative are used. Asymmetric αβ-unsaturated sulphoximines undergo epoxidation with 100% diastereoselectivity. The only exceptions to stereocontrol noted are heavily substituted maleate esters such as di-t-butyl maleate. The αβ-epoxy amides are shown to be valuable sources of the corresponding epoxy ketones by treatment with an organolithium, allowing a stereo- and chemoselective entry in high yield to these useful intermediates.
