as documented by the clicking of carbohydrates with indolealkaloids. The method is also applicable to the conjugation of polymer chains. The linking acetal moiety can be readily cleaved and it is also shown that wavelength-selective coupling and cleavage with acyl silanes bearing a second photoactive moiety is possible. This is documented by a successful polymerization/depolymerization sequence and
A ruthenium-catalyzed C–H alkenylation of aroylsilanes with electron-deficient alkenes was developed, using acylsilane as the directing group. The mild reaction conditions enable the tolerance of a wide scope of functionalities such as OMe, F, Cl, Br and CF3, providing a convenient and highly effective method for the synthesis of styrene derivatives bearing acylsilane. Steroid and heterocycles such
Visible-Light-Induced Catalyst-Free Carboxylation of Acylsilanes with Carbon Dioxide
作者:Zhengning Fan、Yaping Yi、Shenhao Chen、Chanjuan Xi
DOI:10.1021/acs.orglett.1c00435
日期:2021.3.19
Intermolecular carbon–carbon bond formation between acylsilanes and carbondioxide (CO2) was achieved by photoirradiation under catalyst-free conditions. In this reaction, siloxycarbenes generated by photoisomerization of the acylsilanes added to the C═O bond of CO2 to give α-ketocarboxylates, which underwent hydrolysis to afford α-ketocarboxylic derivatives in good yields. Control experiments suggest
Currently, catalytically transferable carbenes are limited to electron-deficient and neutral derivatives, and electron-rich carbenes bearing an alkoxy group (i.e., Fischer-type carbenes) cannot be used in catalyticcyclopropanation because of the lack of appropriate carbene precursors. We report herein that acylsilanes can serve as a source of electron-rich carbenes under palladium catalysis, enabling
Acylsilane represents a valuable synthon in syntheticchemistry. We report on ruthenium(II)-catalyzed ortho-C–H amination of aroylsilanes to provide facile access to syntheticallyuseful imidobenzoylsilanes and tosyl-amidobenzoylsilanes. The protocols, with broad substrate scope and excellent functional group tolerance, are enabled with the weak chelation-assistance of acylsilane via C–H cyclometallation
酰基硅烷代表合成化学中有价值的合成子。我们报告了钌 ( II ) 催化的芳酰基硅烷的邻-C-H 胺化,以提供合成有用的亚氨基苯甲酰基硅烷和甲苯磺酰基-氨基苯甲酰基硅烷的简便途径。该协议具有广泛的底物范围和出色的官能团耐受性,通过C-H 环金属化作用实现了酰基硅烷的弱螯合辅助。