Copper and silicon mediated, HMPA-free, n+3 ring expansions for the construction of medium sized lactones and lactams: short synthesis of (+)-cis-lauthisan
作者:Gary H. Posner、Mark A. Hatcher、William A. Maio
DOI:10.1016/j.tet.2016.05.063
日期:2016.10
enolates for the construction, after oxidative fragmentation, of ring expanded lactones, n+3 atoms in size. Importantly, azido lactones were found to be valuable in an extension of this protocol involving the n+3+p expansion into a series of hydroxyolefinic lactams. We also document a short, stereoselective total synthesis of (+)-cis-lauthisan and a new, cuprate-mediated and HMPA-free procedure for the generation
在本报告中,几个新的环氧化物实例与β-甲硅烷基酮烯酸酯结合在一起,用于氧化断裂后构造n + 3原子大小的扩环内酯。重要的是,发现叠氮基内酯在该方案的扩展中很有价值,该扩展方案涉及将n + 3 + p扩展成一系列羟基烯烃内酰胺。我们还记录了(+)-顺式-lauthisan的短时,立体选择性全合成以及生成β-硅烷基甲硅烷基醚的新型,无铜酸盐介导且无HMPA的程序,可用于环境友好的中型内酯的构建。