Synthesis of Enantioenriched Homopropargylic Sulfonamides by a Three Component Reaction of Aldehydes, Sulfonamides, and Chiral Allenylsilanes
作者:Ryan A. Brawn、James S. Panek
DOI:10.1021/ol901692n
日期:2009.10.1
Enantioenriched allenylsilanes are used as carbon nucleophiles in three-component reactions with in situgenerated N-sulfonylimines to selectively form syn-homopropargylic sulfonamides. The reactions proceed with a variety of aldehyde and sulfonamide reaction partners. These novel reaction products are obtained with useful levels of diastereoselectivity, and the axial chirality of the allenylsilane
对映体富集的丙二烯基硅烷在三组分反应中用作碳亲核试剂,与原位生成的N-磺酰亚胺选择性地形成顺-高炔丙基磺酰胺。反应在各种醛和磺酰胺反应伙伴下进行。这些新的反应产物具有有用的非对映选择性水平,并且丙二烯基硅烷的轴向手性完全转移到点手性,形成具有 >97% ee 的产物。
H<sub>8</sub>-BINOL chiral imidodiphosphoric acid catalyzed highly enantioselective aza-Friedel–Crafts reactions of pyrroles and enamides/imines
The first enantioselective aza-Friedel-Crafts reaction between pyrroles and enamides has been achieved by using novel H8-BINOL type imidodiphosphoric acid catalyst. This methodology was also applied to the highly enantioselective aza-Friedel-Crafts...
An Efficient Synthesis of [(Tosylamino)alkyl]naphthalenols by Nucleophilic Addition of Naphthalen-2-ol with N-Tosyl Imines Using Boron Trifluoride Etherate as Catalyst
[(Tosylamino)alkyl]naphthalenols have efficiently been synthesized by nucleophilic addition of naphthalen‐2‐ol with N‐tosyl imines (derived from both aromatic and aliphatic aldehydes) in the presence of BF3⋅OEt2 as a catalyst at room temperature. The products are formed within 5–9 h in high yields (72–91%).
Tandem Knoevenagel−Michael Addition of Aryl Sulfonimines with Diethyl Malonate for Synthesis of Arylidene Dimalonates
作者:Renhua Fan、Weizi Wang、Dongming Pu、Jie Wu
DOI:10.1021/jo070726e
日期:2007.7.1
A highly efficient, one-flask tandem Knoevenagel-Michael addition reaction of sulfonimines with diethyl malonate in the presence of a catalytic amount of base affords the corresponding arylidene dimalonates in good to excellent yields.