5779-72-6Relevant articles and documents
A Desaturative Approach for Aromatic Aldehyde Synthesis via Synergistic Enamine, Photoredox and Cobalt Triple Catalysis
Caldora, Henry P.,Douglas, James J.,Leonori, Daniele,Turner, Oliver,Zhao, Huaibo
supporting information, (2022/03/15)
Aromatic aldehydes are fundamental intermediates that are widely utilised for the synthesis of important materials across the broad spectrum of chemical industries. Accessing highly substituted derivatives can often be difficult as their functionalizations are generally performed via electrophilic aromatic substitution, SEAr. Here we provide an alternative and mechanistically distinct approach whereby aromatic aldehydes are assembled from saturated precursors via a desaturative process. This novel strategy harnesses the high-fidelity of Diels–Alder cycloadditions to quickly construct multi-substituted cyclohexenecarbaldehyde cores which undergo desaturation via the synergistic interplay of enamine, photoredox and cobalt triple catalysis.
Selective photoredox decarboxylation of α-ketoacids to allylic ketones and 1,4-dicarbonyl compounds dependent on cobaloxime catalysis
Zhang, Hong,Xiao, Qian,Qi, Xu-Kuan,Gao, Xue-Wang,Tong, Qing-Xiao,Zhong, Jian-Ji
supporting information, p. 12530 - 12533 (2020/11/02)
A photoredox/cobaloxime co-catalyzed coupling reaction of α-ketoacids and methacrylates to obtain allylic ketones is described. Without the cobaloxime catalyst, 1,4-dicarbonyl compounds are generated. The cobaloxime catalyst enables dehydrogenation to generate the formation of new olefins. The generality, good substrate scope and mild conditions are good features in the photoredox/cobaloxime catalysis protocol, and this method will provide new opportunities for the functionalization of more olefins.
Methods for preparing benzene-ring-containing compounds from pinacol
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Paragraph 0062; 0063; 0064; 0066; 0067, (2018/08/04)
The invention relates to methods for preparing durene, 1,2,3-trimethylbenzene, o-xylene, pyromellitic acid and trimellitic acid from pinacol. Durene, 1,2,3-trimethylbenzene and o-xylene are prepared through three steps of reaction, and pyromellitic acid and trimellitic acid are prepared through four steps of reaction. A catalytic system used in the invention is green and environment-friendly, andcan be recycled. The raw materials of method, i.e., pinacol, crotonaldehyde, acrolein and crotonate can all be derived from biomass, and are cheap and easily available. All the reaction processes aresimple and are high in activity and selectivity in the dehydration of pinacol and the dehydrogenation, decarbonylation and oxidation of D-A products. The invention provides novel methods for preparingfine chemicals including durene, 1,2,3-trimethylbenzene, o-xylene, pyromellitic acid and trimellitic acid from lignocellulose-based platform chemicals.