A new ring for your indole: An unprecedented copper‐catalyzed enantioselectiveFriedel–Craftsalkylation/N‐hemiacetalization cascade reaction with indoles and β,γ‐unsaturated α‐ketoesters is reported. This mild strategy provides new access to various synthetically and biologically important 2,3‐dihydro‐1H‐pyrrolo[1,2‐a]indoles in a highlyenantioselective manner.
吲哚的新环:据报道,铜与吲哚和β,γ-不饱和α-酮酸酯发生了前所未有的铜催化对映选择性Friedel-Crafts烷基化/ N-半缩醛化级联反应。这种温和的策略以高度对映选择性的方式为各种合成和生物学上重要的2,3-二氢-1 H-吡咯并[1,2- a ]吲哚提供了新途径。
Neighboring Thioether Participation in Bioinspired Radical Oxidative C(sp<sup>3</sup>)–H α-Oxyamination of Pyruvate Derivatives
A bioinspired radical oxidative α-oxyamination of pyruvate with an oxoammonium salt through multiple-site concerted proton–electron transfer process has been developed, which was facilitated by anchoring the mercapoto chains as a “hopping” site at the γ-position of α-keto esters.
diastereo-, and enantioselective Diels–Alderreaction of β,γ-unsaturated α-ketoesters with (E)-1-phenyl dienes has been accomplished by using a stable and easily available chiral N,N′-dioxide/zinc(II) complex as catalyst. Only one isomer of the corresponding cyclohexenes with three chiral centers was obtained in good to excellent yields with excellent ee values under mild reaction conditions. The configurations
Tertiary Amine Mediated Tandem Cross-Rauhut-Currier/Acetalization Reactions: Access to Functionalized Spiro-3,4-Dihydropyrans
作者:Weijun Yao、Yihua Wu、Gang Wang、Yiping Zhang、Cheng Ma
DOI:10.1002/anie.200905091
日期:2009.12.14
γ‐Proton transfer furnished the highly selective title reaction in which cyclic β‐haloenals 1 react with β,γ‐unsaturated α‐ketoesters 2 to generate functionalized spiro‐3,4‐dihydro‐2H‐pyrans 3 having an α‐quaternary carbon center and an adjacent vinyl halide group in skeleton. DBU=1,8‐diazabicyclo[5.4.0]undec‐7‐ene, Tos=4‐toluenesulfonyl.