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)
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
A highly enantioselective construction of δ- and γ-lactone[2,3-b]piperidine skeletons was accomplished by tandem aza-Diels–Alder reaction–hemiacetal formation–oxidation from N-Tos-1-aza-1,3-butadienes and aliphatic dialdehydes.
δ-和的高度对映选择性 γ-内酯[2,3- b ]哌啶通过串联氮杂-狄尔斯-阿尔德反应-半缩醛形成-N -Tos-1-氮杂-1,3-丁二烯和脂肪族二醛的氧化来完成骨架。
unexpected and efficient dominoreaction of N-sulfonyl-1-aza-1,3-dienes with 2-halo-1,3-dicarbonyl compounds to synthesize differently substituted 2,3-dihydrofuran derivatives with excellent regio-, chemo-, and stereoselectivity in moderate to good yields was developed. In this transformation, broad substrate scope was demonstrated, and a plausible mechanism for this novel dominoreaction was given.