Gold-Catalyzed Oxidation/C-H Functionalization of Ynones: Efficient and Rapid Access to Functionalized Polycyclic
Kegong Ji1, Fang Yang2, Shiyue Gao2
1Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Science, Northwest A&F University, 3 Taicheng Road, Yangling 7, 12100, Shaanxi, P.R. China. jikegong@nwsuaf.edu.cn.
Abstract:
An efficient strategy to construct salicyl ketones through gold-catalyzed oxidation/C-H functionalization of ynones is reported. A variety of functionalized salicyl ketones are readily accessed by utilizing this non-diazo approach, thus providing a viable alternative to synthetically useful salicyl ketones with a yield up to 98 %. The α-oxo gold carbenes generated in situ through gold-catalyzed oxidation of ynones can be trapped effectively by internal aryl and heteroaromatic groups. Electronic and steric effects were also investigated in this reaction. The anticancer activity of one salicyl ketone analogue was investigated and its cytotoxicity assays against the PC-3 prostate cancer cell line and SKOV-3 human ovarian carcinoma cell line yield IC50 were 0.81±0.05 and 0.87±0.15 μm, respectively, demonstrating that salicyl ketone analogues showed good anticancer activity.
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