Synthesis and oxygen-atom transfer reactions of 3-hydroperoxy-3,4,4,5,5-pentasubstituted-1,2-dioxolanes
作者:A. Baumstark、Y.-X. Chen、A. Rodriguez
DOI:10.1002/jhet.5570330464
日期:1996.7
A series of 3-hydroperoxy-3,4,4,5,5-pentasubstituted-1,2-dioxolanes 2a-d were synthesized in good yield from the corresponding 3-hydroxy-1,2-dioxolanes by reaction with concentrated hydrogen peroxide in acetonitrile with p-toluenesulfonic acid as catalyst. The 3-hydroperoxy-1,2-dioxolanes were effective oxygen-atom transfer reagents for the oxidation of thioanisole, triethylamine and 2,3-dimethyl-2-butene
通过与浓3-过氧化氢反应,由相应的3-羟基-1,2-二氧戊环高产率地合成了一系列3-氢过氧-3,4,4,5,5-五取代-1,2-二氧戊环2a-d以对甲苯磺酸为催化剂,在乙腈中溶解。3-氢过氧-1,2-二氧戊环是将硫代苯甲醚,三乙胺和2,3-二甲基-2-丁烯分别氧化为亚砜,N-氧化物和环氧化物的有效氧原子转移试剂。反应在温和的条件下发生,被发现总体上是二级反应。测定在氘代氯仿中2a-d氧化硫代苯甲醚的二阶速率常数(k 2)。对于2a,k还测量了N-氧化和环氧化的2个值。发现3-氢过氧-1,2-二氧戊环的反应性比结构相似的环状α-偶氮氢过氧化物低,但比简单的氢过氧化物高得多。假设氧原子转移的机理是通过底物在氢过氧化物的末端氧上的亲核攻击而发生的。氢过氧质子与二氧戊环氧的分子内氢键似乎是非质子介质中反应顺序的原因。