1,721,163 research outputs found
Beta asymmetric induction in the reduction of N-alkylidenesulphinamides. Synthesis of optically active amines
No full textAsymmetric synthesis occurs in the reduction by LiAlH4 of optically active N-alkylidenesulphinamides; the sulphinamides thus obtained can be oxidized to optically active sulphonamides or cleaved to optically active amines of high optical purity
Improved procedure for the purification of PEG bound molecules by the use of trioctylamine
No full textThe use of trioctylamine instead of triethylamine in reactions in which their hydrochlorides are formed simplifies purification and analytical procedures in the synthesis of small organic molecules on PEG supports
Asymmetric selection via addition. Optically active allenic sulphones
No full textRacemic allenic sulphones can be partially resolved by reaction with a deficiency of optically active amines; a catalytic kinetic resolution is also described
Asymmetric induction in the reduction of beta-oxosulphoximides by sodium borohydride
No full textOptically active β-oxosulphoximides have been prepared by reaction of optically active α-metallated NS-dimethyl-S-phenylsulphoximide with carboxylic esters. Their reduction by sodium borohydride is stereoselective, the extent of asymmetric synthesis (up to 50%) depending on steric factors
Enantiomeric excess determination of new classes of chiral sulphur compounds by the use of europium reagents
No full textThe enantiomeric composition of derivatives of new classes of optically active sulphur compounds (variously substituted sulphoxides, sulphoximes, sulphilimines) has been readily determined with the aid of chiral europium shift reagents
Asymmetric induction in the reduction of optically active N-alkylidenesulphinamides by metal hydrides. A new efficient enantioselective route to chiral amines
No full textA series of racemic and optically active N-alkylidenesulphinamides has been prepared and their reduction by metal hydrides studied. The extent of asymmetric synthesis mainly depends on the nature of the reducing species; the best results (up to 92% of stereoselectivity) are obtained with alkoxy-lithium aluminium hydrides. A new, highly enantioselective synthesis of amines is described
Catalytic Enantioselective Homogeneous Reactions Mediated by Transition Metal Lewis Acids
No full text- …
