Diastereoselective Trifluoromethylation of Chiral<i>N</i>-(Tolylsulfinyl)imines in the Presence of Lewis Bases
作者:Yoshikazu Kawano、Teruaki Mukaiyama
DOI:10.1246/cl.2005.894
日期:2005.7
A diastereoselctive trifluoromethylation of chiral N-(tolylsulfinyl)imines with (trifluoromethyl)trimethylsilane in the presence of Lewis bases such as tetrabutylammonium acetate or phenoxide proceeded smoothly to afford the corresponding trifluoromethylated adducts in good yields.
Lewis base-catalyzed diastreoselective Mannich-type reaction between ketene silyl acetals and chiral sulfinimines proceeded smoothly to afford the corresponding β-amino carbonyl compounds in good to high yields with high selectivities.
Synthesis of chiral non-racemic 2-arylpyrrolines by a [3+2] cycloaddition route
作者:Thiagarajan Balasubramanian、Alfred Hassner
DOI:10.1016/0040-4039(96)01176-8
日期:1996.8
A new and efficient diastereoselective (upto 76% de) synthesis of 2-aryl-3-pyrroline derivatives 3a-f has been achieved by [3+2] cycloaddition of allylsulfone 1 and non-racemic sulfinimines 2. Separation of the diastereomers led to optically pure 2(R)-pyrrolines (62–72% yield). The N-sulfinyl auxiliary can be removed with TFA.
Synthesis of Sulfinimines by Direct Condensation of Sulfinamides with Aldehydes Using Cs<sub>2</sub>CO<sub>3</sub>as an Activating and Dehydrating Reagent
Chiral sulfinimines were prepared from chiral sulfinamides and aldehydes in CH 2 Cl 2 in the presence of cesium carbonate as an amine-activating and dehydrating reagent.
A Highly Diastereoselective MgI<sub>2</sub>-Mediated Ring Expansion of Methylenecyclopropanes
作者:Mark E. Scott、Wooseok Han、Mark Lautens
DOI:10.1021/ol048769u
日期:2004.9.1
A highly diastereoselective MgI2-mediated ring expansion of methylenecyclopropane amides to functionalized pyrrolidines has been developed using chiral aromatic sulfinimines. The 2,3,4-trisubstituted pyrrolidines were isolated in generally good to excellent yields and in excellent diastereoselectivities for aromatic and heterocyclic sulfinimines.