Molecular Discovery and Innovation, H. Lundbeck A/S, Ottiliavej 9, 2500, Valby, Denmark.
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark.
Chemistry. 2023 Jun 22;29(35):e202300265. doi: 10.1002/chem.202300265. Epub 2023 May 3.
Herein we report on the decarboxylative alkenylation between alkyl carboxylic acids and enol triflates. The reaction is mediated by a dual catalytic nickel and iridium system, operating under visible light irradiation. Two competing catalytic pathways, from the excited state iridium photocatalyst, are identified. One is energy transfer from the excited state, resulting in formation of an undesired enol ester. The desired pathway involves electron transfer, resulting in decarboxylation to ultimately give the target product. The use of a highly oxidizing iridium photocatalyst is essential to control the reactivity. A diverse array of enol triflates and alkyl carboxylic acids are investigated, providing both scope and limitations of the presented methodology.
在此，我们报告了一种在双催化镍和铱体系作用下，通过可见光照射，实现羧酸与烯醇三氟甲磺酸酯之间脱羧烯基化的反应。该反应存在两种竞争的催化途径，均源于铱光催化剂的激发态。其中一种是能量从激发态转移，导致形成不需要的烯醇酯。而所需的途径则涉及电子转移，最终实现脱羧，得到目标产物。使用强氧化态的铱光催化剂对于控制反应性是至关重要的。研究了一系列不同的烯醇三氟甲磺酸酯和羧酸，为所提出的方法提供了广泛的适用范围和限制。
