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。
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.
Facile Synthesis of <i>E</i>‐Diiodoalkenes: H<sub>2</sub>O<sub>2</sub>‐Activated Reaction of Alkynes with Iodine
作者:Alexander O. Terent'ev、Dmitry A. Borisov、Igor B. Krylov、Gennady I. Nikishin
DOI:10.1080/00397910701545171
日期:2007.9.1
activate iodine in the addition reaction with triple bonds. A facile and technologically straightforward procedure was developed for the synthesis of E‐diiodoalkenes based on the reaction of alkynes with an I2–H2O2 system in THF. Selective iodination of terminal and internal alkynes containing electron‐donating and electron‐withdrawing substituents afforded 16 E‐diiodoalkenes in yields up to 89%.
Mechanism and Scope of the Base-Induced Dehalogenation of (<i>E</i>)-Diiodoalkenes
作者:Daniel Resch、Chang Heon Lee、Siew Yoong Tan、Liang Luo、Nancy S. Goroff
DOI:10.1002/ejoc.201402992
日期:2015.2
nucleophiles have induced the elimination of iodine from (E)-diiodoalkenes to form alkynes under surprisingly mild conditions. The iodide anion is particularly efficient, and can drive the reaction to completion in less than 1 hour at room temperature in a polar aprotic solvent. Detailed investigations have suggested the reaction has a bimolecular polar mechanism. The deiodination reaction can be driven to completion
(NH4)2S2O8-Mediated Diiodination of Alkynes with Iodide in Water: Stereospecific Synthesis of (E)-Diiodoalkenes
作者:Can-Cheng Guo、Qing Jiang、Jing-Yu Wang
DOI:10.1055/s-0034-1379910
日期:——
A new approach to the stereospecific diiodination of alkynes under mild conditions has been developed. This protocol employs ammonium persulfate as an oxidant and iodide as an iodine source, and provides a highly efficient and general method for the preparation of a broad range of (E)-diiodoalkenes in water.