The regioselectivity of the Suzuki couplings of several 4,5- and 3,4-dibromopyrrole-2-carboxylate esters has been studied. In general, regioselectivity can be achieved for initial coupling at the more electron-deficient site (C5 and C3, respectively). At the same time, conversions are often modest (40-60%) and attempts to force the reactions to higher conversions often lead to competitive dicoupling.
Modular Total Synthesis of the 5/5-Spirocyclic Spiroindimicins
作者:Ankush Banerjee、Tiffany A. Brisco、Zhen Zhang、Alexander A. Busse、Krissty Sumida、Myles W. Smith
DOI:10.1021/acs.orglett.3c03131
日期:2023.12.1
Total syntheses of the 5/5-spirocyclic indoline alkaloids (±)-spiroindimicins B, C, D, E, F, and G have been achieved via a modular approach. Our route features direct coupling of halogenated pyrrolemetal and isatin partners, Suzuki coupling to append the indole unit, Lewis acid-mediated spirocyclization, and divergent functionalization to give various family members. These syntheses are concise (six
通过模块化方法实现了 5/5-螺环二氢吲哚生物碱 (±)-spiroindimicins B、C、D、E、F 和 G 的全合成。我们的路线的特点是卤化吡咯金属和靛红伴侣的直接偶联、铃木偶联以附加吲哚单元、路易斯酸介导的螺环化以及不同的官能化以产生各种家族成员。这些合成很简洁(来自商业材料的六到七个步骤)并且非常适合模拟合成。