Cyclooctanone synthesis via a formal [6+2] cycloaddition reaction of a dicobalt acetylene complex
作者:Katsuhiko Mitachi、Tadashi Shimizu、Masaaki Miyashita、Keiji Tanino
DOI:10.1016/j.tetlet.2010.05.120
日期:2010.7
An efficient formal [6+2] cycloaddition reaction of a new six-carbon unit with enol silyl ether was developed on the basis of a dicobalt hexacarbonyl propargyl cation species. Under the influence of EtAlCl2, 6-benzoyloxy-2-(triisopropylsilyloxy)-1-hexen-4-yne-dicobalthexacarbonyl reacted with enol triisopropylsilyl ethers to yield 7-(triisopropylsilyloxy)-3-cyclooctyn-1-one-dicobalthexacarbonyl derivatives
在二钴六羰基炔丙基阳离子种类的基础上,开发了一种新的六碳单元与烯醇甲硅烷基醚的有效的正式[6 + 2]环加成反应。在EtAlCl 2的影响下,6-苯甲酰氧基-2-(三异丙基甲硅烷氧基)-1-己烯-4-炔-二钴六羰基化合物与烯醇三异丙基甲硅烷基醚反应生成7-(三异丙基甲硅烷氧基)-3-环辛炔-1-酮-二杂六羰基衍生物良品率高。与环状烯醇甲硅烷基醚以及无环烯醇甲硅烷基醚的反应表现出非常高的非对映选择性。