Synthesis of o-Arylenedizinc Compounds and Their Synthetic Applications

邻亚芳基锌化合物的合成及其合成应用

基本信息

批准号：
07640787
负责人：
TAKAGI Kentaro
金额：
$ 1.54万
依托单位：
Okayama University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07640787/
关键词：
o-Arylenedizinc Compounds Aryl Triflates o-Bromophenylzinc Compound

项目摘要

Structures of arenes, possessing two different side chains at adjacent positions of benzene ring, are observed in numerous organic compounds. One general way to construct such structures might utilize SE or SN type replacement reaction using synthetic equivalents of o-phenylene dianion, dication, or 1-anion 2-cation as benzo segments with appropriate reagents. In this research, we tried to synthesize o-arylenedizinc compounds, intending to use them as the synthetic equivalent of o-arylene dianion in the synthesis of unsymmetrically 1,2-disubstituted arenes.We have already reported on the synthesis of o-phenylenedizinc compound. However, it appeared that similar route will be less effective for the synthesis of o-arylenedizinc compounds because of the limited availability of 1,2-diiodoarenes. Then, new access to o-arylenedizinc compounds was investigated. That is, regioselective iodination of phenols, followed by triflation of the hydroxyl group, affords aryl triflates containing iodo s … More ubstituent at ortho position. Various o-arylenedizinc compounds were obtained in good yields by the reaction of the aryl triflates with zinc powder.Next, the reaction of o-phenylenedizinc compound with electrophilic reagents was examined. When one equivalent of such reagent as iodobenzene or benzoyl chloride was applied to the reaction in the presence of palladium(0) catalyst containing tris(2,4,6-tri-methoxyphenyl)phosphine or tri(o-tolyl)phosphine as a ligand, formal SE reaction took place selectively at one electrophilic side between two possible centers to afford arylzinc compounds in high yields. Further addition of second reagents to the resulting solutions induce the catalytic reactions once again, providing unsymmetrically 1,2-disubsutituted arenes in good yields.For the first time, o-bromophenylzinc compound as a novel synthetic equivalent of o-phenylene 1-anion 2-cation was prepared by the reaction of o-bromoiodobenzene with zinc powder and was applied to the palladium(0)-catalyzed cross-coupling. Its consecutive treatment with electrophilic reagents like aryl halides or aryl halides and then with nucleophilic reagents like potassium cyanide, alkyne, or arylzinc compounds afforded various unsymmetrically 1,2-disubstituted arenes in good yields. Less

在许多有机化合物中观察到在苯环的相邻位置具有两个不同侧链的芳烃结构，构建此类结构的一种通用方法可能是利用邻苯二撑二阴离子、二价阴离子或二价阴离子的等效合成物进行 SE 或 SN 型取代反应。 1-阴离子2-阳离子作为苯并片段在本研究中，我们尝试合成邻亚芳基二阴离子化合物，打算将其用作邻亚芳基二阴离子的合成等价物。不对称1,2-二取代芳烃的合成。我们已经报道了邻亚苯基二甲基化合物的合成，但是，由于1的可用性有限，类似的路线似乎不太有效。然后，研究了邻亚芳基化合物的新途径，即苯酚的区域选择性碘化，然后进行羟基的三氟甲磺酸化。通过三氟甲磺酸芳基酯与锌粉的反应，得到了邻位含有碘取代基的芳基三氟甲磺酸酯，以良好的收率获得了各种邻亚苯基二甲磺酸化合物。当一当量的碘苯或苯甲酰氯等试剂在存在下进行反应时。含有三(2,4,6-三甲氧基苯基)膦或三(邻甲苯基)膦作为配体的钯(0)催化剂，在两个可能的中心之间的一个亲电子侧选择性地发生正式SE反应，得到芳基锌化合物向所得溶液中进一步添加第二试剂再次引发催化反应，以良好的产率提供不对称的1,2-二取代芳烃。首次通过邻溴碘苯与锌粉反应制备了邻溴苯基锌化合物作为邻亚苯基1-阴离子2-阳离子的新型合成等价物，并将其应用于钯(0)催化的交叉偶联。它用亲电试剂如芳基卤或芳基卤连续处理，然后用亲核试剂如氰化钾、炔烃、或芳基锌化合物以良好的产率提供各种不对称1,2-二取代芳烃。