1,5-Hydrogen Atom Transfer/Surzur–Tanner Rearrangement: A Radical Cascade Approach for the Synthesis of 1,6-Dioxaspiro[4.5]decane and 6,8-Dioxabicyclo[3.2.1]octane Scaffolds in Carbohydrate Systems
作者:Elisa I. León、Ángeles Martín、Adrián S. Montes、Inés Pérez-Martín、María del Sol Rodríguez、Ernesto Suárez
DOI:10.1021/acs.joc.1c01376
日期:2021.11.5
alkoxyl radicals were generated by the reaction of the corresponding N-alkoxyphthalimides with group 14 hydrides [n-Bu3SnH(D) and (TMS)3SiH], and in comparative terms, the reaction was also initiated by visible light photocatalysis using the Hantzsch ester/fac-Ir(ppy)3 procedure. Special attention was devoted to the influence of the relative stereochemistry of the centers involved in the radical sequence
已经在一系列具有 3 -C- ( α, β- d , l - 吡喃葡萄糖基)1-丙醇和C -(α- d , l -吡喃葡萄糖基)甲醇结构,由手性池d - 和l - 糖制备。使用乙酰氧基和二苯氧基磷酸酯氧基作为离去基团可有效构建 10-deoxy-1,6-dioxaspiro[4.5]decane 和 4-deoxy-6,8-dioxabicyclo[3.2.1]octane 骨架。烷氧基自由基由相应的N反应生成-烷氧基邻苯二甲酰亚胺与第 14 族氢化物 [ n -Bu 3 SnH(D) 和 (TMS) 3 SiH],比较而言,该反应也由使用 Hantzsch 酯/ fac -Ir(ppy) 3程序的可见光光催化引发. 特别关注自由基序列中涉及的中心的相对立体化学对反应结果的影响。将BF 3 •Et 2 O 作为催化剂添加到自由基序列中导致所需双环缩酮的产率显着增加。