Metal-Free Synthesis of 4-Chloroisocoumarins by TMSCl-Catalyzed NCS-Induced Chlorinative Annulation of 2-Alkynylaryloate Esters.,The Journal of Organic Chemistry

当前位置： X-MOL 学术 › J. Org. Chem. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Metal-Free Synthesis of 4-Chloroisocoumarins by TMSCl-Catalyzed NCS-Induced Chlorinative Annulation of 2-Alkynylaryloate Esters.
The Journal of Organic Chemistry ( IF 3.3 ) Pub Date : 2019-12-04 , DOI: 10.1021/acs.joc.9b02793
Krissada Norseeda ₁ , Nattawadee Chaisan ₁ , Charnsak Thongsornkleeb ₁ , Jumreang Tummatorn ₁ , Somsak Ruchirawat ₁

Affiliation

4-Chloroisocoumarins can be conveniently prepared from 2-alkynylaryloate esters via the activation of alkynes by electrophilic chlorine, generated in situ from N-chlorosuccinimide (NCS) in the presence of 10 mol % trimethylsilyl chloride (TMSCl), which leads to 6-endo-dig-selective chlorinative annulation to give the desired products in moderate to quantitative yields. The procedure employs readily available reagents and can be conveniently carried out on a wide scope of substrates under mild conditions (0 °C to rt). Furthermore, the reaction is scalable for gram-scale preparation of 4-chloroisocoumarins. Additionally, 4-bromo- and 4-iodoisocoumarins can be prepared in moderate to good yields by replacing NCS with N-bromosuccinimide (NBS) and N-iodosuccinimide (NIS), respectively.

中文翻译：

通过TMSCl催化的NCS诱导的2-炔基芳基酸酯的氯化环化反应，无金属合成4-氯异香豆素。

4-氯异香豆素可方便地由2-炔基芳基酸酯通过亲电氯活化炔烃而制得，该亲电基氯在10 mol％三甲基甲硅烷基氯（TMSCl）存在下由N-氯代琥珀酰亚胺（NCS）原位生成，从而生成6-内-dig-selective氯化法制环，以中等到定量的产量获得所需的产品。该方法使用了容易获得的试剂，并且可以在温和的条件下（0°C至rt）在各种底物上方便地进行。此外，该反应可扩展用于克级制备4-氯异香豆素。另外，通过分别用N-溴代琥珀酰亚胺（NBS）和N-碘代琥珀酰亚胺（NIS）代替NCS，可以以中等至良好的产率制备4-溴-和4-碘异香豆素。

更新日期：2019-12-04

点击分享查看原文

点击收藏

阅读更多本刊新发论文