Asymmetric Hetero-Diels–Alder Reaction of Danishefsky’s Dienes with α-Carbonyl Esters Catalyzed by an Indium(III)–PyBox Complex
作者:Bei Zhao、Teck-Peng Loh
DOI:10.1021/ol400841s
日期:2013.6.21
An efficient catalytic enantioselective hetero-Diels–Alderreaction of Danishefsky’s dienes with α-carbonyl esters using a chiral In(III)–pybox complex has been demonstrated. This protocol offers several advantages, including mildreaction conditions, relatively low catalyst loading, and good to excellent enantioselectivities. Furthermore, the absolute configurations of the new alkynyl-containing products
Novel Synthesis of 2-Oxo-3-butynoates by Copper-Catalyzed Cross-Coupling Reaction of Terminal Alkynes and Monooxalyl Chloride
作者:Minjie Guo、Dao Li、Zhaoguo Zhang
DOI:10.1021/jo0353076
日期:2003.12.1
A general and efficient Cu(I)-catalyzed cross-coupling reaction of terminalalkynes and monooxalyl chloride for the synthesis of 2-oxo-3-butynoates and 2-oxo-3-butynoamides was developed. Readily available starting materials, the mild reaction conditions, wide functional group tolerance, and the obviation of stoichiometric organolithium or magnesium reagents combine to highlight this reaction.
Iron(III) chloride hexahydrate promotes a cascade of transformations on a Petasis condensation product that sets up the right dihydropyran precursors of valuable Relenza congeners.