A nickel-catalyzed asymmetric Suzuki–Miyaura cross-coupling of racemic 3-bromo-phthalides and arylboronic acids was realized for the synthesis of diverse chiral 3-aryl-phthalides in moderate to excellent reaction yields. The reaction proceeded in a stereoconvergent manner and high enantioselectivities were observed for most examined examples. A number of functional groups like aldehyde, ester and bromide
d π-conjugated quinoids were synthesized by alkoxide-mediated rearrangementreaction of the respective alkene precursors, followed by air oxidation. This new protocol allows access to quinoidal compounds with variable termini and cores. The resulting quinoids all show LUMO levels below -4.0 eV and molar extinction coefficients above 105 L mol-1 cm-1 . The optoelectronic properties of these compounds
通过各烯烃前体的醇盐介导的重排反应,然后进行空气氧化,合成了一系列的1,3-茚满二酮封端的π-共轭醌。该新协议允许访问具有可变末端和核心的喹啉化合物。所得的醌类化合物均显示LUMO水平低于-4.0 eV,摩尔消光系数高于105 L MOl-1 cm-1。这些化合物的光电特性可以通过调节中心核以及归因于涉及芳基末端的整个分子骨架上的离域边界分子轨道的芳基末端来调节。制作了电子迁移率高达0.38 cm2 V-1 s-1的n沟道有机薄膜晶体管,显示出这种新型醌类化合物作为有机半导体的潜力。
Enantioselective Synthesis of Ten-Membered Lactones via Palladium-Catalyzed [5 + 5] Annulation
作者:Liu Shi、Qiang Xiong、Shu-Yi Wu、Yang Li、Peng Shen、Ji Lu、Guang-Yao Ran
DOI:10.1021/acs.orglett.3c00374
日期:2023.3.31
products but with a great synthetic challenge. Based on the principle of vinylogy, novel types of cyclic vinylogous anhydrides have been designed as five-carbon carbonyl synthons, further applied in [5 + 5] annulation with vinylethylene carbonates under chiral palladium catalysis. This strategy features excellent regioselectivity, mild conditions, and broad substrate scope, affording a range of spiro
Chiral Isothiourea‐Catalyzed Acylative Dynamic Kinetic Resolution of 3‐Hydroxyphthalides for Enantioselective Synthesis of Phthalidyl Esters
作者:Zeyang Hao、Wei Lin、Zi‐Qi Yuan、Wei Zhang、Xin Li
DOI:10.1002/cjoc.202400382
日期:2024.10
display a diverse array of biological activities. We report herein a highly efficient dynamic kinetic resolution of 3-hydroxyphthalides by chiral isothioureas (ITUs) catalyzed asymmetric acylation, facilitating the effective synthesis of a variety of chiral phthalidyl esters with good yields and enantioselectivities. Notably, this reaction features mild reaction conditions, expansive substrate scope as well