Oxidant- and additive-free simple synthesis of 1,1,2-triiodostyrenes by one-pot decaroboxylative iodination of propiolic acids
作者:Subhankar Ghosh、Rajat Ghosh、Shital K. Chattopadhyay
DOI:10.1016/j.tetlet.2020.152378
日期:2020.10
A metal- and oxidant-free facile synthesis of a range of 1,1,2-triiodostryrene derivatives has been developed which utilizes a simple decarboxylative triiodination of propiolicacids using molecular iodine and sodium acetate in a one-pot manner. Electron-withdrawing or donating substituents in the aryl rings display marginal influence on the course of the reaction. Mechanistic investigation reveals
Regio- and Stereoselective Synthesis of 1,2-Dihaloalkenes Using In-Situ-Generated ICl, IBr, BrCl, I2, and Br2
作者:Xiaojun Zeng、Shiwen Liu、Yuhao Yang、Yi Yang、Gerald B. Hammond、Bo Xu
DOI:10.1016/j.chempr.2020.03.011
日期:2020.4
2-trans-dihalogenation of alkynes with an unprecedented substrate scope and exclusive regio- and stereoselectivity. This versatile dihalogenation system—a combination of NX1S electrophile and alkali metal halide (MX2) in acetic acid—is applicable for diverse categories of alkynes (electron-rich or poor alkynes, internal and terminalalkynes, or heteroatoms such as O-, N-, S-substituted alkynes). The hydrogen
我们描述了炔烃的无催化剂的1,2-反式二卤代反应,具有空前的底物范围和排他性和立体选择性。这种多功能的二卤化系统-NX 1 S亲电试剂和乙酸中的碱金属卤化物(MX 2)的组合-适用于各种类型的炔烃(富电子或弱炔烃,内部和末端炔烃,或杂原子,例如O- ,N-,S-取代的炔烃)。氢键供体溶剂乙酸对于就地生成X 1 X 2亲电试剂(包括ICl,IBr,BrCl,I 2和Br 2)是必不可少的。
A Study on Reactions of an Alkynylsilane with Oxone-KX (X = Cl, Br, I) and Its One-pot Transformation into an Amide/Ester
Oxyhalogenation reactions of a variety of alkynylsilanes were studied using oxone as mild oxidant and KCl, KBr, and KI as halogen sources. In this study, reaction of an alkynylsilane with oxone-KX (X = Cl or Br) produced trichloromethyl/tribromomethyl ketones in high yields. Under similar conditions, however, reactions of alkynylsilanes with oxone-KI were found to give exclusively 1,2,2-triiodovinyl
Efficient synthesis of 1-iodoalkynes <i>via</i> Al<sub>2</sub>O<sub>3</sub> mediated reaction of terminal alkynes and <i>N</i>-iodosuccinimide
作者:Ming Yao、Jingjing Zhang、Sen Yang、Hangxing Xiong、Li Li、E. Liu、Hong Shi
DOI:10.1039/d0ra00251h
日期:——
Iodination of terminalalkynes using N-iodosuccinimide (NIS) in the presence of γ-Al2O3 was developed to afford 1-iodoalkynes with good to excellent yields (up to 99%). This described approach featured excellent chemoselectivity, good functional group tolerance, and utilization of an inexpensive catalyst.
开发了在 γ-Al 2 O 3存在下使用N-碘代琥珀酰亚胺 (NIS) 对末端炔进行碘化,以提供良好至优异产率(高达 99%)的 1-碘炔。这种方法具有优异的化学选择性、良好的官能团耐受性以及使用廉价催化剂的特点。
Methyl group migration in the reactions of alkynyltrialkylborates
作者:Andrew Pelter、Robert A. Drake
DOI:10.1016/s0040-4039(00)80450-5
日期:1988.1
It is shown that the methyl group cannot be used as a cheap, non-migrating group in the reactions of alkynyltrialkylborates with electrophiles. However, trimethylborane can be used as a methylboronating agent for alkynes, given the right choice of solvent, and this may be of use in terpene synthesis.