with cyclic imino esters catalyzed by a bifunctional chiral tertiary amine has been developed, which provides an efficient access to optically active β-position functionalized pyrrolidin-2-one derivatives in both high yield and enantioselectivity (up to 78% yield and 95 : 5 er). This is the first catalytic method to access chiral β-functionalized pyrrolidin-2-one via a direct organocatalytic approach
Here, we report a convenient access to diastereoselectivesynthesis of polysubstituted pyrrolidines bearing a unique spiro quaternary center at the C-2 position and another quaternary center at C-4. The synthesis system, CuII/P, N-Ligand-catalyzed 1, 3-dipolar cycloaddition, by employing homoserine lactone derived cyclic imino esters as the dipoles and α, α, β-trisubstituted olefins as the dipolarophlies
在这里,我们报告了一个方便的方法,可方便地进行多取代的吡咯烷的非对映选择性合成,该取代基在C-2位置带有一个独特的螺旋季中心,在C-4位置具有另一个季中心。通过使用高丝氨酸内酯衍生的环状亚氨基酯作为偶极,以α,α,β-三取代烯烃为偶极子,Cu II / P,N-配体催化的1,3-偶极环加成反应的合成系统提供了exo -spiro-吡咯烷类具有良好的收率,高的非对映选择性(高达> 98:2 dr),并且在广泛的底物上表现良好。
exo-Selective construction of spiro-[butyrolactone-pyrrolidine] via 1,3-dipolar cycloaddition of azomethine ylides with α-methylene-γ-butyrolactone catalyzed by Cu(i)/DTBM-BIPHEP
作者:Qing-Hua Li、Tang-Lin Liu、Liang Wei、Xiang Zhou、Hai-Yan Tao、Chun-Jiang Wang
DOI:10.1039/c3cc45493b
日期:——
An expedient access to optically active spiro-[butyrolactone-pyrrolidine] was successfully developed via an unprecedented Cu(I)-catalyzed exo-selective 1,3-DC of azomethine ylides with α-methylene-γ-butyrolactone, which exhibited high diastereoselectivity (>98â:â2), excellent enantioselectivity (96â>99% ee) and a broad substrate scope under mild conditions.
Enantioselective Synthesis of Polysubstituted Spiro-nitroprolinates Mediated by a (<i>R</i>,<i>R</i>)-Me-DuPhos·AgF-Catalyzed 1,3-Dipolar Cycloaddition
作者:Alberto Cayuelas、Ricardo Ortiz、Carmen Nájera、José M. Sansano、Olatz Larrañaga、Abel de Cózar、Fernando P. Cossío
DOI:10.1021/acs.orglett.6b01273
日期:2016.6.17
The synthesis of constrained spirocycles is achieved effectively by means of 1,3-dipolar cyclodditions employing α-imino γ-lactones as azomethine ylide precursors and nitroalkenes as dipolarophiles. The complex formed by (R,R)-Me-DuPhos 18 and AgF is the most efficient bifunctional catalyst. Final spiro-nitroprolinates cycloadducts are obtained in good to moderate yields and both high diastereo- and
Stereoselective Construction of Spiro(butyrolactonepyrrolidines) by Highly Efficient Copper(I)/TF-BiphamPhos-Catalyzed Asymmetric 1,3-Dipolar Cycloaddition
作者:Tang-Lin Liu、Zhao-Lin He、Hai-Yan Tao、Chun-Jiang Wang
DOI:10.1002/chem.201103876
日期:2012.6.25
Pyrrole into one: The catalytic asymmetric1,3‐dipolarcycloaddition of cyclic aldimino esters has been accomplished for the first time, enabling facile access to spiro(butyrolactonepyrrolidines) containing one spiro quaternary center and three tertiary stereogenic centers (see scheme). The catalytic system performs well with a broad range of substrates, furnishing synthetically useful adducts in high