Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, NY 13244, USA.
Org Biomol Chem. 2022 Mar 9;20(10):2131-2136. doi: 10.1039/d2ob00127f.
-Alkylation of isatins can be achieved utilizing trichloroacetimidate electrophiles and a Lewis acid catalyst. These reactions provide access to -alkyl isatins, versatile scaffolds which are often employed in the synthesis of pharmaceutical lead structures as well as natural products. Secondary trichloroacetimidates that are precursors to stabilized carbocations provided excellent yields of the isatin product. Substitution was well tolerated on the isatin, although reduced reactivity was observed with C7-substitution, likely due to the steric effects. Solvent effects can be used to favor -alkylation under similar reaction conditions.
利用三氯乙腈作为亲电试剂和路易斯酸催化剂可以实现靛红的烷基化。这些反应提供了 - 烷基靛红，这是一种多功能的支架，常用于药物先导结构和天然产物的合成。作为稳定碳正离子前体的仲三氯乙腈可以很好地得到靛红产物。尽管在 C7 取代时观察到反应活性降低，可能是由于空间位阻的影响，但在靛红上的取代反应得到了很好的容忍。可以使用溶剂效应在相似的反应条件下有利于 - 烷基化。
