作者:Miguel Yus、Rosario Torregrosa、Isidro Pastor
DOI:10.3390/90500330
日期:——
The protocol of lithiation by means of lithium and a catalytic (5% molar) amount of DTBB (4,4’-di-tert-butylbiphenyl), applied to ω-chloro ortho ester 6 under Barbier-type conditions gives, after final acid-catalyzed methanolysis, the corresponding functionalized esters 8 or 9 (for chlorotrimethylsilane as electrophile) or, after ortho ester deprotection and acid catalyzed treatment, the δ-lactones 11. The procedure is also practical for bicyclic ortho esters 14: the β-chloro OBO ester derivate generates the γ- lactones 15 and the γ-chloro OBO ester gives corresponding esters 8.
通过
锂和催化量(5%摩尔)的DT
BB(4,4'-二叔丁基
联苯)进行
锂化反应的协议,应用于ω-
氯代原酸
酯6在Barbier型条件下,经最终酸催化的
甲醇分解反应,得到相应的功能化
酯8或9(以
氯三
甲基硅烷为亲电试剂),或经过原酸
酯脱保护和酸催化处理,得到δ-内
酯11。该方法也适用于双环原酸
酯14:β-
氯代OBO
酯衍
生物产生γ-内
酯15,而γ-
氯代OBO
酯则得到相应的
酯8。