new unified synthetic protocol to (±)-crinine, (±)-crinamine, and (±)-6a-epi-crinamine from the Diels−Alder cycloadduct of 3-(3,4-methylenedioxyphenyl)-5-bromo-2-pyrone with TBS vinyl ether. The requisite 3-(3,4-methylenedioxyphenyl)-5-bromo-2-pyrone was prepared from the C3-selective Stille coupling reaction of 3,5-dibromo-2-pyrone. Also noted is that the vinyl bromide can be used as a handle for further
我们设计了一种新的统一合成方案,用于由3-(3,4-亚甲基二氧苯基)-5-的Diels-Alder环加成物中的(±)-可兰宁,(±)-可可胺和(±)-6a-表位-可可胺。
溴-2-
吡喃酮与TBS
乙烯基醚。由3,5-二
溴-2-
吡喃酮的C3-选择性Stille偶联反应制备必需的3-(3,4-亚甲基二氧苯基)-5-
溴-2-
吡喃酮。还应注意的是,
溴乙烯可以用作进一步衍生化的处理。