ABSTRACT
An ICl-mediated highly chemo- and regioselective functional group interconversion from methyl homopropargyl ether to α-iodo-γ-chloro-ketone is reported. Density functional theory (DFT)-calculated reaction coordinate and potential energy surface support the high chemo-selectivity observed for the formation of α-iodo-γ-chloroketone over furan. The five-membered oxonium ring formation-ring opening mechanism is a potential template for the preparation of polyfunctionalized carbonyl compounds.
Subject(s)
Ethers , Levulinic AcidsABSTRACT
3,5-Disubstituted isoxazoles and isoxazolines undergo an iron-catalyzed reductive ring-opening in aged N-methyl-2-pyrrolidone (NMP). 5-Hydroxy-N-methyl-2-pyrrolidone generated in situ via a simple activation of commercial NMP acts as the hydrogen donor in the iron-catalyzed transfer hydrogenation reaction. It is the first example employing a combination of an iron catalyst and 5-hydroxy-N-methyl-2-pyrrolidone as reducing agents in a transfer hydrogenation reaction. The protocol is highly efficient for the synthesis of ß-enaminones and 1,3-diketones, providing a versatile route for the preparation of these 1,3-difunctional compounds bearing diversified substitution patterns.
ABSTRACT
An auto-tandem palladium catalysis from halogen-substituted isoxazoles and Michael acceptors is described. It involves two mechanistically distinct palladium-catalyzed reactions, a Heck reaction and a rearrangement, leading to 2-azafluorenones. It is the first example of palladium-catalyzed ring opening of isoxazoles and rearrangement of the ß-imino ketone ring-opening product.
