Asymmetric Mannich Reaction and Construction of Axially Chiral Sulfone-Containing Styrenes in One Pot from α-Amido Sulfones Based on the Waste–Reuse Strategy
作者:Dongmei Li、Yu Tan、Lei Peng、Shan Li、Nan Zhang、Yidong Liu、Hailong Yan
DOI:10.1021/acs.orglett.8b02087
日期:2018.8.17
simultaneous asymmetric Mannichreaction and the construction of axially chiral sulfone-containing styrenes in one pot from α-amidosulfones based on the waste–reuse strategy was demonstrated. A series of chiral β-amino diesters and axially chiral sulfone-containing styrenes with various functional groups were synthesized in good to excellent yields and enantioselectivities under mild conditions. In
synthetic equivalents of a variety of α‐carboxylate anions. Phase‐transfer catalysis (PTC) enabled their mild deprotonation and catalytic asymmetric addition to highly reactive imines generated in situ from α‐amidosulfones (see scheme; Pg=protecting group). The synthetic utility of the products was demonstrated by their straightforward transformation into a range of β‐amino acid derivatives.
Bismuth Triflate-Catalyzed Addition of Allylsilanes to N-Alkoxycarbonylamino Sulfones: Convenient Access to 3-Cbz-Protected Cyclohexenylamines
作者:Thierry Ollevier、Zhiya Li
DOI:10.1002/adsc.200900710
日期:2009.12
Bismuth triflate was found to be an efficient catalyst in the Sakurai reaction of allyltrimethylsilanes with N-alkoxycarbonylaminosulfones. The reaction proceeded smoothly with a low catalyst loading of Bi(OTf)3⋅4 H2O (2–5 mol%) to afford the corresponding protected homoallylic amines in very good yields (up to 96%). A sequential allylation reaction followed by ring-closing metathesis delivers 6–8
Enantioenriched Naphthoquinone Mannich Bases by Organocatalyzed Nucleophilic Additions to in situ Formed Imines
作者:Bernhard Westermann、Muhammad Ayaz
DOI:10.1055/s-0029-1219946
日期:2010.6
Organocatalytic nucleophilic addition of 2-hydroxylnaphthaquinone to imines is reported. This new route can be used to produce enantioenriched Mannich bases with excellent yields and moderate enantioselectivities.