Palladium‐Catalyzed Regioselective and Diastereoselective
<i>C</i>
‐Glycosylation by Allyl‐Allyl Coupling
作者:Junhao Li、Nan Zheng、Xuelun Duan、Rui Li、Wangze Song
DOI:10.1002/adsc.202001136
日期:2021.2.2
A Pd‐catalyzed C‐glycosylation reaction was developed by allyl‐allyl coupling process using Achmatowicz rearrangement products as donors and methylcoumarins as acceptors under mild conditions. This method featured regio‐ and diastereoselectivities, stereodivergent synthesis of C‐glycosides. The glycosyl donors with controlled stereodiversity and glycosyl acceptors with fluorescent performace further
Iridium-catalyzed direct asymmetric vinylogous allylic alkylation
作者:Chang-Yun Shi、Jun-Zhao Xiao、Liang Yin
DOI:10.1039/c8cc07249c
日期:——
alkylation of α,β-unsaturated lactones (including coumarins) was achieved with excellent regio- and enantioselectivity. Transformations of the product were carried out by means of the versatile terminal olefin and lactonemoieties. The synthetic application of the present methodology was showcased by the asymmetric synthesis of an advanced synthetic Merck intermediate toward a new drug candidate.
Vinylogous Nucleophiles Bearing the Endocyclic Double Bond in the Allylic Alkylation with Morita-Baylis-Hillman Carbonates
作者:Dorota Kowalczyk、Łukasz Albrecht
DOI:10.1002/adsc.201701185
日期:2018.2.1
nucleophilicity in the allylic alkylation with Morita‐Baylis‐Hillman carbonates can be accomplished through the endocyclic double bond in 3‐cyano‐4‐methylcoumarins. The developed reaction provides a straightforward access to functionalized coumarin derivatives of biological and synthetic relevance. Target, highly functionalized products have been chemoselectively and efficiently obtained in very high yield
Chiral Hypervalent Bromine(III) (Bromonium Salt): Hydrogen- and Halogen-Bonding Bifunctional Asymmetric Catalysis by Diaryl-λ<sup>3</sup>-bromanes
作者:Yasushi Yoshida、Takashi Mino、Masami Sakamoto
DOI:10.1021/acscatal.1c04070
日期:2021.11.5
Bromonium salts, which are hypervalent bromine reagents, have been explored as being strong electrophiles owing to their extremely high nucleofugalities. Only one example of their catalytic application has been reported by our group; however, their chiral versions have not yet been researched. Halogen-bonding (XB) has been widely applied in chemistry; however, its successful application to highly enantioselective
溴鎓盐是高价溴试剂,由于其极高的离核性,已被研究为强亲电试剂。我们小组只报道了一个催化应用的例子;然而,他们的手性版本尚未被研究。卤素键合(XB)在化学中得到了广泛的应用;然而,其在高对映选择性路易斯酸催化中的成功应用尚未实现。在此,我们报告了手性环状二芳基溴鎓盐的设计和开发。这些催化剂实现了高度对映选择性的路易斯酸 XB 催化,提供了高达 96% ee 的产物。
Highly Enantioselective Catalytic Vinylogous Propargylation of Coumarins Yields a Class of Autophagy Inhibitors
作者:Hao Xu、Luca Laraia、Laura Schneider、Kathrin Louven、Carsten Strohmann、Andrey P. Antonchick、Herbert Waldmann
DOI:10.1002/anie.201706005
日期:2017.9.4
A highly enantioselective copper‐catalyzed vinylogous propargylic substitution has been developed. Aromatic and aliphatic propargylic esters react smoothly with substituted coumarins under mild reactionconditions to give the desired products with excellent yields and enantioselectivities. Subsequent single‐step transformations enable the synthesis of a wide range of multifunctional and diverse compounds