42764-63-6Relevant academic research and scientific papers
Diastereoselective Reductions of β-Keto Sulfoximines
Johnson, Carl R.,Stark, Charles J.
, p. 1196 - 1200 (2007/10/02)
(S)-β-Keto sulfoximines have been prepared by butyllithium-mediated condensation of (+)-(S)-N,S-dimethyl-S-phenylsulfoximine with nitriles.The β-keto sulfoximines on treatment with a variety of reducing agents afforded β-hydroxy sulfoximines with varying diastereomeric ratios.Highest asymmetric inductions were observed with gaseous diborane.A sulfoximine-borane complex is suggested as an intermediate.Raney nickel desulfurization of the β-hydroxy sulfoximines afforded secondary alcohols with optical purities in the 18-69percent range.
Asymmetric Induction in the Reaction of β-Oxosulphoximides by Sodium Borohydride
Annunziata, Rita,Cinquini, Mauro,Cozzi, Franco
, p. 1109 - 1111 (2007/10/02)
Optically 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
S-Ethenylsulfoximine Derivatives. Reagents for Ethylenation of Protic Nucleophiles
Johnson, Carl R.,Lockard, James P.,Kennedy, Eugene R.
, p. 264 - 271 (2007/10/02)
The preparation of S-vinyl and S-(2-substituted)ethenyl derivatives of sulfoximines is described.Vinyl-, (2-phenylethenyl)-, (2,2-diphenylethenyl)-, (2-methyl-1-propenyl)-, (dimethylamino)phenyloxosulfonium fluoroborates were found to undergo an addition-elimination reaction sequence with protic nitrogen and carbon nucleophiles, resulting in ethylenation of the nucleophile and N,N-dimethylbenzenesulfinamide.Primary amines gave aziridines, enamines gave cyclopropyl derivatives of iminium salts or pyrrolidinium salts, anions of active methylene compounds gave dihydrofurans and/or cyclopropanes, and anions of nitroalkanes gave cyclic nitronic esters and/or nitrocyclopropanes.In several cases vinyl salts were generated in situ from β-methoxyoxosulfonium salts.Treatment of (-)-(S)-dimethylamino)phenyl(trans-2-phenylethenyl)oxosulfonium fluoroborate with methyl cyanoacetate in methanol containing sodium methoxide gave, in 81percent yield, (+)-(1S,2R)-methyl 1-cyano-2-phenylcyclopropanecarboxylate of 25.5percent optical purity.The same salt upon treatment with methyl nitroacetate gave, in 95percent yield, methyl 4-phenyl-3-isoxazolinecarboxylate 2-oxide with 33percent enantiomeric excess.Cyclopropanes were formed upon treatment of S-methyl-S-(trans-2-phenylethenyl)-N-(p-tolylsulfonyl)sulfoximine with anions of active methylene compounds.
