C−H Insertion Approach to the Synthesis of <i>e</i><i>ndo,</i><i>e</i><i>xo</i>-Furofuranones: Synthesis of (±)-Asarinin, (±)-Epimagnolin A, and (±)-Fargesin
作者:Richard C. D. Brown、Carole J. R. Bataille、Gordon Bruton、Jeremy D. Hinks、Nigel A. Swain
DOI:10.1021/jo015829q
日期:2001.10.1
A series of novel 5-aryl-4-aryloxymethyl-3-diazotetrahydrofuran-2-ones (12, 24, and 35a/b) have been prepared and found to undergo regio- and stereoselective C-H insertion reactions to afford 2,6-diaryl-3,7-dioxabicyclo[3.3.0]octane-8-ones (18, 26, and 36a/b) with endo,exo stereochemistry. Subsequent reduction of the lactone ring and cyclization of the resulting diols 27 and 37a/b permitted the synthesis
已经制备了一系列新颖的5-芳基-4-芳氧基甲基-3-重氮四氢呋喃-2-酮(12、24和35a / b),发现它们进行了区域和立体选择性CH插入反应,从而得到2,6-二芳基具有内,外立体化学反应的-3,7-二氧杂双环[3.3.0]辛烷-8-酮(18、26和36a / b)。随后内酯环的还原和所得二醇27和37a / b的环化,可以合成三种内生的呋喃呋喃木聚糖内酯:天麻素(2),fargesin(3)和表甘露聚糖A(4)。在生产关键的重氮化合物24和35a / b的过程中,开发了一种改进的Ghosez酮亚胺-烯烃环化方法,该方法需要最大程度地减少酸敏感性官能团(例如存在于苯酚中的富电子苄基醚)的分解目标化合物2-4。