In Search of Catalytic Antioxidants—(Alkyltelluro)phenols, (Alkyltelluro)resorcinols, and Bis(alkyltelluro)phenols
作者:Jia-fei Poon、Vijay P. Singh、Lars Engman
DOI:10.1021/jo400703w
日期:2013.6.21
2-(alkyltelluro)resorcinols. Bis(alkyltelluro)phenols were accessed by allowing the trianion produced from the reaction of 2,6-dibromophenol with 5 equiv of tert-butyllithium to react with dialkyl ditellurides. The novel phenolic compounds were found to inhibit azo-initiated peroxidation of linoleic acid much more efficiently than α-tocopherol in a two-phase peroxidation system containing excess N-acetylcysteine
通过邻-(烷基碲基)苯酚淬灭过氧自由基的机理比正式的H原子转移更为复杂。为了改进这一概念,我们制备了(烷基碲)间苯二酚和双(烷基碲)苯酚,并评估了它们的催化链断裂和预防性抗氧化性能。使由2-溴苯酚和3当量的叔丁基锂产生的原位形成的三价阴离子与二烷基二碲化物反应,以低收率提供邻-(烷基碲基)苯酚。2- Bromoresorcinols与4当量的处理后叔丁基锂类似地得到2-(烷基碲)间苯二酚。通过使由2,6-二溴苯酚与5当量的叔丁基锂反应产生的三阴离子与二烷基二碲化物反应来获得双(烷基碲)苯酚。发现在包含过量N的两相过氧化系统中,新型酚类化合物比α-生育酚更有效地抑制亚油酸的偶氮引发的过氧化。-乙酰半胱氨酸在水相中作为化学计量的硫醇还原剂。大多数(烷基碲)酚和间苯二酚只能在89–228分钟内抑制过氧化,而某些双(烷基碲)酚则具有更高的可再生性,并提供> 410分钟的保护。还评估了新型(烷基碲)