Potassium <i>tert</i>-Butoxide Promoted Annulation of 2-Alkynylphenyl Propargyl Ethers: Selective Synthesis of Benzofuran and 12<i>H</i>-Benzoannulene Derivatives
作者:Tamiris B. Grimaldi、Davi F. Back、Gilson Zeni
DOI:10.1021/jo4020062
日期:2013.11.1
We present here our results on potassiumtert-butoxide promoted annulation reactions of 2-alkynylphenyl propargyl ethers to give two different types of heterocycles: 3-benzyl-2-alkynylbenzofurans and 12H-benzoannulenbenzo[b]furans. A series of functionalized 2-alkynylphenyl propargyl ethers were efficiently cyclized by potassiumtert-butoxide to the corresponding products. The optimized reaction conditions
我们在这里介绍关于叔丁醇钾促进的2-炔基苯基炔丙基醚的环化反应以产生两种不同类型的杂环的结果:3-苄基-2-炔基苯并呋喃和12 H-苯并环戊并苯并[ b ]呋喃。叔丁基钾有效地环化了一系列官能化的2-炔基苯基炔丙基醚-丁氧化物制得相应产物。优化的反应条件可耐受多种官能团,包括富电子,贫电子和N杂环底物。通过控制溶剂和温度获得选择性的产物形成。当在室温下使用THF时,只能获得3-苄基-2-炔基苯并呋喃衍生物,而在60°C下使用DMF时,则可以选择性地生成12 H-苯并环戊烯[ b ]苯并呋喃。
Regioselective and Stereoselective Synthesis of Pyridine-Fused Benzoxepine Derivatives by Intramolecular Reductive Heck Cyclization[1]
作者:Shovan Mondal、Sudarshan Debnath
DOI:10.1002/jhet.2357
日期:2016.1
11‐dihydro[2]benzoxepino[4,3‐b]pyridine derivatives via Pd(0) catalyzed intramolecularreductive Heck cyclization is reported. The method offers the regioselective and stereoselective synthesis of highly functionalized pyridine‐fused benzoxepine derivatives in 75–85% yields under mild conditions. Chemoselective Sonogashira coupling is utilized for the synthesis of cyclization precursors. The stereochemistry
为6,11-二氢[1]苯并氧杂并[4,3的合成的有效方法b ]通过钯(0)吡啶衍生物催化的分子内还原的环化的Heck报道。该方法可在温和条件下以75-85%的产率对高度官能化的吡啶融合的苯并西庚因衍生物进行区域选择性和立体选择性合成。化学选择性的Sonogashira偶联被用于环化前体的合成。通过单晶X射线衍射证实了6,11-二氢[2]苯并氧杂庚并[4,3- b ]吡啶衍生物的环外双键的立体化学。N-Pd(II)相互作用的缺乏导致二苯并xepine衍生物的环外双键的反向立体化学。