据报道,前所未有的Mn I / Ag I中继催化(乙烯基)芳烃与α-重氮酮的C(sp 2)-H / C(sp 3)-H偶联,其中重氮基被用作无痕助剂控制区域选择性。具有挑战性的β-(杂)芳基/烯基酮是通过这种操作简单的方法获得的。级联过程合并了脱氮,卡宾重排,CH活化和加氢芳基化/加氢烯基化。该方法的鲁棒性已在制备规模上得到证明,并应用于天然产物的后期多样化。
Triethylgallium deprotonated cyclic and acyclicketones at 125-175 degrees C without forming carbonyl addition products, and the resulting gallium enolates underwent facile C-benzoylation and an aldol reaction. Unsymmetrical ketones were preferentially enolized at the methylene moiety, which was under kinetic control. [reaction: see text]
A carbon–carbon bond was formed at the β-position of cyclicketones in a one-pot manner by oxidation with N-tert-butylbenzenesulfinimidoyl chloride, followed by the reaction of malonic acid esters or potassium cyanide.
Alkali Carbonates Improve β,β-Diaryl Serine-Catalyzed Enantioselective α-Fluorination of β-Dicarbonyl Compounds
作者:Katsuki Endo、Daiki Tomon、Satoru Arimitsu
DOI:10.1021/acs.joc.3c00730
日期:2023.7.7
cyclic and acyclic β-dicarbonylcompounds, including β-diketones, β-ketoesters, and β-ketoamides. The reactions with β,β-diaryl serines as primary amine organocatalysts were enhanced by adding alkali carbonates, such as Na2CO3 or Li2CO3, and enabled the reaction to be conducted with only 1.1 equiv of Selectfluor. The optimal conditions afforded the α-fluorinated β-dicarbonylcompounds in 50–99% yield
在此,我们报道了环状和无环β-二羰基化合物(包括β-二酮、β-酮酯和β-酮酰胺)的高度对映选择性α-氟化。通过添加碱金属碳酸盐,例如Na 2 CO 3或Li 2 CO 3 ,可以增强以β,β-二芳基丝氨酸作为伯胺有机催化剂的反应,并且使得反应能够仅用1.1当量的Selectflu进行。最佳条件提供了 α-氟化 β-二羰基化合物,产率为 50-99%,具有优异的对映选择性(高达 98% ee)。
Huenig,S. et al., Chemische Berichte, 1967, vol. 100, p. 3996 - 4009