Rhodium-catalyzed cycloaddition of carbonyl ylides for the synthesis of spiro[furo[2,3-<i>a</i>]xanthene-2,3′-indolin]-2′-one scaffolds
作者:B. V. Subba Reddy、E. Pravardhan Reddy、B. Sridhar、Y. Jayaprakash Rao
DOI:10.1039/c6ra05661j
日期:——
An intramolecular cycloaddition of oxonium ylides generated from 3-diazooxindole and a bifunctional substrate i.e. 2-methyl-2-(4-methylpent-3-en-1-yl)-2H-chromene-3-carbaldehyde has been achieved using 5 mol% of Rh2(OAc)4 to produce highly substituted 3,3,5a-trimethyl-3a,5,5a,11b-tetrahydro-3H,4H-spiro[furo[2,3-a]xanthene-2,3′-indolin]-2′-ones in good yields with high diastereoselectivity. This is
由3- diazooxindole生成氧鎓叶立德的分子内环和双功能基板即2-甲基-2-(4-甲基戊-3-烯-1-基)-2- ħ色烯-3-甲醛已经实现使用5摩尔%的Rh 2(OAc)4产生高度取代的3,3,5a-三甲基-3a,5,5a,11b-四氢-3 H,4 H-螺[呋喃[2,3- a ]氧杂蒽-2, 3'-吲哚啉] -2'-非对映选择性好,收率高。这是从容易获得的前体合成生物学相关的多环骨架的第一个例子。