Synthesis of Novel Spirooxindole and Spirodihydroqinoline by Domino [3+2] Cycloaddition and Acetylenedicarboxylate Promoted Ring-expansion Reaction" />
串联[3+2]环加成和丁炔二甲酸酯参与的扩环反应合成新型螺吲哚酮和螺二氢喹啉类化合物
Abstract：Multicomponent reaction and domino reaction are widely used in organic synthesis because of their using readily available raw materials, convenient synthetic method, less reaction steps and separation processes. a simple and efficient method for synthesizing spiro compounds via domino reaction was reported in this paper. The one-pot [3+2] cycloaddition reaction of L-thioproline, isatins and chalcones and sequential ring-expansion reaction with dimethyl but-2-ynedioate in refluxing methanol resulted in sulfanyl-containing polycyclic spirooxindole and spirodihydroqinoline derivatives. The spiro compounds were characterized by IR, HR-MS, 1H and 13C NMR spectroscopy and were confirmed by single crystal structures. The formation mechanism of the two compounds included domino ring-opening and annulation process. This reaction has the advantages of using readily available substrates, simple operation and high atomic economy.
