Metal-free, hydroacylation of CC and NN bonds via aerobic C–H activation of aldehydes, and reaction of the products thereof
作者:Vijay Chudasama、Ahmed R. Akhbar、Karim A. Bahou、Richard J. Fitzmaurice、Stephen Caddick
DOI:10.1039/c3ob41632a
日期:——
In this report, a thorough evaluation of the use of aerobically initiated, metal-free hydroacylation of various CC and NN acceptor molecules with a wide range of aldehydes is presented. The aerobic-activation conditions that have been developed are in sharp contrast to previous conditions for hydroacylation, which tend to use transition metals, peroxides that require thermal or photochemical degradation, or N-heterocyclic carbenes. The mildness of the conditions enables a number of reactions involving sensitive reaction partners and, perhaps most significantly, allows for α-functionalised chiral aldehydes to undergo radical-based hydroacylation with complete retention of optical purity. We also demonstrate how the resulting hydroacylation products can be transformed into other useful intermediates, such as γ-keto-sulfonamides, sultams, sultones, cyclic N-sulfonyl imines and amides.
Metal-Containing Ionic Liquids as Efficient Catalysts for Hydroxymethylation in Water
作者:Katharina Bica、Peter Gaertner
DOI:10.1002/ejoc.200800323
日期:2008.7
The iron-containing ionicliquid butylmethylimidazolium tetrachloroferrate (bmim-FeCl4) proved to be an efficient and recyclable catalyst for the hydroxymethylation of β-keto esters using aqueous formaldehyde and a low catalyst loading of up to 0.1 mol-% without co-solvents or additional surfactants. An useful and high-yielding approach to hydroxymethylated keto esters as well as to 3-disubstitued
Abstract An easy approach to the synthesis of substituted unsaturated lactones is described, and the reactions of these compounds with nucleophiles leading to the formation of useful intermediates are reported.