Cu(I)-Catalyzed Highly Enantioselective [3 + 3] Cycloaddition between Two Different 1,3-Dipoles, Phthalazinium Dicyanomethanides and Iminoester-Derived Azomethine Ylides
The Cu(I)-catalyzed highly enantioselective [3 + 3] cycloadditionbetween two different 1,3-dipoles, phthalazinium dicyanomethanides and iminoester-derived azomethine ylides, has been achieved under mild reaction conditions, providing novel chiral heterocyclic compounds, 2,3,4,11b-tetrahydro-1H-pyrazino[2,1-a]phthalazine derivatives, in high yields with excellent diastereo- and enantioselectivies (up
在温和的反应条件下,已实现了Cu(I)催化的两个不同的1,3-偶极,酞菁双氰胺和亚氨基酯衍生的偶氮甲碱的高对映选择性[3 + 3]环加成反应,提供了新颖的手性杂环化合物2,3 ,4,11b-四氢-1 H-吡嗪并[ 2,1- a ]酞嗪衍生物,高收率,具有出色的非对映和对映选择性(高达99%收率,99%ee,> 20:1 dr)。
Diversity Oriented Synthesis of Pyrrolidines via Natural Carbohydrate Solid Acid Catalyst
作者:Atul Kumar、Garima Gupta、Suman Srivastava
DOI:10.1021/cc100007a
日期:2010.7.12
carbohydrate scaffold catalyzed diastereoselective synthesis of functionalized pyrrolidines have been developed via 1,3-dipolarcycloaddition of azomethine ylides derived from α-imino esters with dienes or dipolarophiles. Naturally most abundant carbohydrates, like cellulose and starch, were converted into their sulfuric acid derivative, which are exhibiting efficient catalytic properties, along with excellent
The tandem nucleophilic addition–cycloaddition reaction has been developed for the synthesis of functionalized imidazolidine derivatives. A variety of α-iminoesters and aryne precursors were well tolerated under the mild reaction conditions. This asymmetric cycloaddition afforded imidazolidine derivatives with high yields, complete regioselectivities, and excellent diastereo- and enantioselectivities
Cu(<scp>i</scp>)-Catalyzed asymmetric <i>exo</i>-selective synthesis of substituted pyrrolidines <i>via</i> a 1,3-dipolar cycloaddition reaction
作者:Rayhan G. Biswas、Sumit K. Ray、Vinod K. Kannaujiya、Rajshekhar A. Unhale、Vinod K. Singh
DOI:10.1039/d1ob00494h
日期:——
An (R)-DM-BINAP/Cu(CH3CN)4BF4 complex catalyzed exo-selective asymmetric 1,3-dipolarcycloaddition (1,3-DCA) reaction of imino esters with α,β-unsaturated pyrazoleamides has been developed. A series of highly functionalized pyrrolidines with multiple stereogenic centers were obtained with good yields and diastereoselectivities and excellent enantioselectivities (up to 99% ee).
Highly fluorescent 1,2-dihydropyrimido[1,6-α]indole: an efficient metal free synthesis and photophysical study
作者:Tapas Das、Anirban Kayet、Ruchika Mishra、Vinod K. Singh
DOI:10.1039/c6cc05378e
日期:——
A metal free route to highly fluorescent 1,2-dihydropyrimido[1,6-[small alpha]]indole derivatives has been developed via base catalyzed aldol followed by Mannich reaction of indole-2-carboxaldehyde with azomethine ylides at room temperature. This transformation...