雪松烷二醇硼酸酯的合成及其不对称同系化反应  

Preparation and Homologation of Cedranediol Boronic Esters

作　　者：宋一麟[1] 范育波[1] 丁宗彪[1] 王全瑞[1] 陶凤岗[1] 

机构地区：[1]复旦大学化学系,上海200433

出　　处：《化学学报》1999年第5期527-532,共6页Acta Chimica Sinica

基　　金：自然科学基金(29672006)资助项目

摘　　要：报道了手性试剂雪松烷二醇硼酸酯(3)的合成及其和二氯甲基锂进行不对称同系化反应,生成α-氯代硼酸酯4R和4S,其R/S的比率在25:1以上,并且有手性助剂容易回收的特点.通过对同系化产物4cR的单晶X衍射分析,发现其分子中的1,3-二氧杂-2-硼杂环戊烷为非平面结构,文中就这一结构特点进行了初步讨论,解释了雪松烷二醇硼酸酯容易水解的原因.(-)-Cedranediol boronic esters 3, a series of asymmetric homologation reagents were prepared from a new chiral director ( - )-cedranediol 1 and boronic acids. 1 was easily synthesized by the dihydroxylation of ( - )-a-cedrene 2 with OsO4. Homologation of cedranediol boronic esters 3 with (dichloromethyl) lithium resulted in (R)-a-chloro boronic esters 4, with R/S-ratios over 25:1. It is easy to recover cedranediol for its boronic esters prone to rapid hydrolysis. The absolute configuration of cedranediol (R)-1-chloro-2-phenylethylboronate 4cR was determined by X-ray diffraction. The distortion of the five-membered 1,3,2-dipxaborolane ring of 4cR was found and discussed.

关 键 词：雪松烷二醇硼酸酯 不对称同系化 α-氯代硼酸酯 

分 类 号：O627.31[理学—有机化学] O626.1[理学—化学]