58538-94-6Relevant academic research and scientific papers
Photoredox Catalytic Phosphite-Mediated Deoxygenation of α-Diketones Enables Wolff Rearrangement and Staudinger Synthesis of β-Lactams
Jiang, Zhiyong,Li, Haijun,Wei, Guo,Yang, Hui
supporting information, p. 19696 - 19700 (2021/08/03)
A novel visible-light-driven catalytic activation of C=O bonds by exploiting the photoredox chemistry of 1,3,2-dioxaphospholes, readily accessible from α-diketones and trialkyl phosphites, is reported. This mild and environmentally friendly strategy provides an unprecedented and efficient access to the Wolff rearrangement reaction which traditionally entails α-diazoketones as precursors. The resulting ketenes could be precisely trapped by alcohols/thiols to give α-aryl (thio)acetates and by imines to afford the valuable β-lactams in up to 99 % yields.
Palladium/copper-catalyzed Di-α-arylation of acetic acid esters
Song, Bingrui,Himmler, Thomas,Goossen, Lukas J.
supporting information; experimental part, p. 1688 - 1694 (2011/09/14)
A bimetallic palladium/copper catalyst system was found to effectively promote the diarylation of alkyl acetates with aryl halides under unprecedentedly mild conditions. The phenanthroline-copper-phosphine catalyst stabilizes the enolate intermediate to the extent that the deprotonation of esters can be achieved even with the mild base potassium phosphate. The palladium tri-tert-butylphosphine co-catalyst mediates the coupling of the resulting copper enolate with a wide variety of aryl halides with selective formation of the corresponding diarylacetic acid esters. Copyright
Concave reagents, 21: Selective acylations of primary and secondary alcohols by ketenes
Schyja, Wolfgang,Petersen, Soenke,Luening, Ulrich
, p. 2099 - 2105 (2007/10/03)
Concave pyridines 1 were used to catalyze the addition of primary and secondary alcohols to ketenes 4, and the kinetic data of these catalyses were determined. In inter- and intramolecular competitions the use of 1e-g led to improved selectivities for the acylation of primary alcohols in comparison with secondary alcohols. All primary alcohols react at comparable rates. Observed rate constants were correlated with Taft's Es values. The starting materials and products were fully characterized. VCH Verlagsgesellschaft mbH, 1996.
