Enantioselective [4 + 1]-Annulation of α,β-Unsaturated Imines with Allylic Carbonates Catalyzed by a Hybrid <i>P</i>-Chiral Phosphine Oxide–Phosphine
作者:Hanyuan Li、Jiesi Luo、Bojuan Li、Xizhen Yi、Zhengjie He
DOI:10.1021/acs.orglett.7b02800
日期:2017.10.20
A highly enantio- and diastereoselective [4 + 1]-annulation reaction between α,β-unsaturated imines and allylic carbonates has been realized under the catalysis of a novel hybrid P-chiral phosphine oxide–phosphine, providing enantioenriched polysubstituted 2-pyrrolines in good to excellent yields and up to 99% ee. Based on Han’s methods, the catalyst featuring a sole P(O)-chirality in the molecule
Enantioselective [4+2] cycloaddition reaction of α,β-unsaturated imine and methyl vinyl ketone catalyzed by chiral phosphine
作者:Ge Wang、Rukeya Rexiti、Feng Sha、Xin-Yan Wu
DOI:10.1016/j.tet.2015.04.076
日期:2015.6
New bifunctional phosphines were prepared as chiral organocatalysts for the enantioselective [4+2] cycloaddition between α,β-unsaturated imines and methylvinylketone. In the presence of 10 mol % of amide-phosphine, the [4+2] cycloaddition reaction was achieved in good-to-excellent yields (up to 95%) and diastereoselectivities (up to 99:1 dr) with moderate-to-good enantioselectivities (up to 82% ee)
Catalytic Asymmetric [4+2] Annulation Initiated by an Aza-Rauhut-Currier Reaction: Facile Entry to Highly Functionalized Tetrahydropyridines
作者:Zugui Shi、Peiyuan Yu、Teck-Peng Loh、Guofu Zhong
DOI:10.1002/anie.201203316
日期:2012.7.27
Under control: The first example of chiral amino phosphine catalysts for the title reaction between vinyl ketones and N‐sulfonyl‐1‐aza‐1,3‐dienes has been developed. Under ambient conditions, this protocol provides straightforward access to densely functionalized, enantioenriched tetrahydropyridines with high levels of sterecontrol in good to excellent yields.
Synthesis of Highly Substituted Pyridines through Copper-Catalyzed Condensation of Oximes and α,β-Unsaturated Imines
作者:Wei Wen Tan、Yew Jin Ong、Naohiko Yoshikai
DOI:10.1002/anie.201704378
日期:2017.7.3
A copper-catalyzed condensation reaction of oxime acetates and α,β-unsaturated ketimines to give pyridine derivatives is reported. The reaction features mild conditions, high functional-group compatibility, and high regioselectivity with respect to unsymmetrical oxime acetates, thus allowing the preparation of a wide range of polysubstituted pyridines, many of which are not readily accessible by conventional
Chiral Bicyclic Bridgehead Phosphoramidite (Briphos) Ligands for Asymmetric Rhodium-Catalyzed 1,2- and 1,4-Addition
作者:Ansoo Lee、Hyunwoo Kim
DOI:10.1021/acs.joc.6b00033
日期:2016.5.6
A complementary solution for Rh-catalyzed enantioselective 1,2- and 1,4-arylation with two structurally related chiralligands is reported. A chiral bicyclic bridgehead phosphoramidite (briphos) ligandderived from 1-aminoindane was efficient for the 1,2-arylation of N-sulfonyl imines, while that derived from 1,2,3,4-tetrahydro-1-naphthylamine was efficient for 1,4-arylation of α,β-unsaturated cyclic