Palladium-Catalyzed\nDomino Carboetherification Reactions:\nSynthesis of Bis-Heterocycles Bearing Isoxazoline and Methyleneindole\nMotifs

A novel and highly efficient Pd-catalyzed approach for\nthe synthesis\nof bis-heterocycles featuring both isoxazoline and methyleneindole\nmotifs is demonstrated. The in situ formation of vinyl Pd(II) species\nthrough an alkyne-tethered carbamoyl chloride cyclization is crucial,\nand the innovative Pd-catalyzed carboetherification of β,γ-unsaturated\noximes with vinyl Pd(II) species has been developed. This method is\nnot only operationally straightforward but also exhibits a broad substrate\nscope and excellent functional group tolerance.