Highly regioselective and stereoselective synthesis of C-Aryl glycosides <i>via</i> nickel-catalyzed <i>ortho</i>-C–H glycosylation of 8-aminoquinoline benzamides
C-Arylglycosides are of high value as drug candidates. Here a novel and cost-effective nickel catalyzed ortho-CAr–H glycosylation reaction with high regioselectivity and excellent α-selectivity is described. This method shows great functional group compatibility with various glycosides, showing its synthetic potential. Mechanistic studies indicate that C–H activation could be the rate-determining
C-芳基糖苷作为候选药物具有很高的价值。本文描述了一种新颖且经济高效的镍催化邻-C Ar -H 糖基化反应,具有高区域选择性和优异的 α-选择性。该方法与各种糖苷表现出良好的官能团相容性,显示出其合成潜力。机理研究表明 C-H 激活可能是速率决定步骤。
Modular Synthesis of Aryl Thio/Selenoglycosides via the Catellani Strategy
We described a novel palladium-catalyzed domino procedure for the preparation of (hetero)aryl thio/selenoglycosides. Readily available (hetero)aryl iodides and easily accessible 1-thiosugars/1-selenosugars are utilized as the substrates. Meanwhile, 10 types of sugars are quite compatible with this reaction with good regio- and stereoselectivity, high efficiency, and broad applicability (up to 89%,
Glycosyl chlorides, useful as glycosyl donors in glycoside synthesis and precursors in organic synthesis, can be easily prepared under solvent-free conditions by exposing a sugar hemiacetal to an equimolar mixture of PPh3 and hexachloroacetone at 70 °C. The reaction affords products in high yields and short times, and is tolerant of a wide range of commonly adopted protecting groups.
glycosides were applied to the reaction smoothly, and N-alkyl (primary, secondary and tertiary) C4-glycosidic indoles can also be obtained by this method. In terms of mechanism, the key ANP intermediates characterized by X-ray single-crystal diffraction and further controlled experiments proved that the migration-insertion of smNBDs with phenylpalladium intermediate endows them with high chemo- and