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。
Cobalt-catalyzed stereoselective iodosulfonylation and diiodination of alkynes via oxidation of potassium iodide in air
作者:Nobukazu Taniguchi
DOI:10.1016/j.tet.2018.02.004
日期:2018.3
Cobalt-catalyzed iodosulfonylation of alkynes can be achieved using sodium sulfinates in the presence of KI. This procedure produces numerous stereoselective (E)-β-iodoalkenyl sulfones with good yields and suppresses the formation of diiodoalkenes. Furthermore, when this reaction is performed in the absence of sodium sulfinates, the expected (E)-diiodoalkenes are obtained.
An aqueous medium-controlled stereospecific oxidative iodination of alkynes: efficient access to (<i>E</i>)-diiodoalkene derivatives
作者:Rammurthy Banothu、Swamy Peraka、Srujana Kodumuri、Durgaiah Chevella、Krishna Sai Gajula、Vasu Amrutham、Divya Rohini Yennamaneni、Narender Nama
DOI:10.1039/c8nj03929a
日期:——
A new and versatile approach for the stereospecific iodination of alkynes has been developed in aqueous media. Scale-up reactions (up to 5 g) established the proficiency of this protocol and highlight the feasibility of large scale reactions.
Ready access to organoiodides: Practical hydroiodination and double-iodination of carbon-carbon unsaturated bonds with I2
作者:Jing Xiao、Li-Biao Han
DOI:10.1016/j.tet.2019.05.019
日期:2019.6
By using I2 or I2/H3PO3 system, various alkenes and alkynes were converted to the corresponding alkyl and alkenyl iodides in good yields. In the presence of I2, alkynes could be di-iodinated using H2O as the solvent in air at room temperature. This method also features the simple work-up procedure since the pure product could be obtained by extraction. Additionally, for the first time, combining with
通过使用I 2或I 2 / H 3 PO 3体系,将各种烯烃和炔烃以良好的产率转化为相应的烷基碘和烯基碘。在存在I 2的情况下,可以在室温下于空气中使用H 2 O作为溶剂将炔烃二碘化。由于可以通过萃取获得纯产物,因此该方法还具有简单的后处理程序。此外,首次将无毒廉价的膦酸H 3 PO 3与烯烃和炔烃成功加氢碘化,为有机碘的合成提供了一种简单实用的方法。
A new and efficient method for the synthesis of α,α-dihaloketones by oxyhalogenation of alkynes using oxone®–KX (X = Cl, Br, or I)
A simple and efficient method for the preparation of α,α-dichloroketones, α,α-dibromoketones, and α,α-diiodoketones by oxyhalogenation of alkynes using oxone® and KX (X = Cl, Br, or I) is described.