开发了一种简单的合成烷基苯乙烯基硒化物的方法。这种方法涉及到在原位生成selenolate阴离子通过单罐和三步协议,其中KSeCN和烷基卤化物之间的亲核取代,得到在第一步骤中相应的烷基硒,通过另一ķ给予二烷基联硒化物3 PO 4 -辅助反应。随后的还原产生与取代的(E,Z)-β-苯乙烯基卤化物,得到相应的乙烯基硒化物,并保留了立体化学结构,产率中等至优异。该方法不需要催化剂,在空气气氛下且在短的反应时间内进行,并且不含二硒化物和恶臭和对空气敏感的烷基硒醇作为起始原料。
Pd-Catalyzed Cyanoselenylation of Internal Alkynes: Access to Tetrasubstituted Selenoenol Ethers
作者:Marcel Bürger、Sebastian H. Röttger、Maximilian N. Loch、Peter G. Jones、Daniel B. Werz
DOI:10.1021/acs.orglett.0c01582
日期:2020.7.2
The intra- and intermolecular synthesis of selenium-substituted acyclic and heterocyclic acrylonitrile derivatives is presented. The 1,2-difunctionalization of several internal alkynes substituted not only by aliphatic and aromatic residues but also by heteroelements is realized by the Pd-catalyzed activation of aromatic and aliphatic selenocyanates. A high functional group tolerance allows straightforward
bibenzyls and related ethane derivatives in high yields. Other diselenides were easily caused to cleave to give various aromatic and aliphatic olefins in good yields together with elemental selenium. Lepidopterene, [2.2]paracyclophane, and benzocyclobutene were prepared by thermal cleavage of their corresponding phenylselenomethyl-substituted compounds as an application of the pyrolysis concerned.
Highly chemoselective synthesis of functionalized diselenides from alkyl halides using benzyltriethylammonium tetrathiomolybdate
作者:Kandikere R. Prabhu、Srinivasan Chandrasekaran
DOI:10.1039/a701512g
日期:——
A variety of functionalized selenocyanates generated in situ
from the corresponding alkyl halides undergo a facile reductive coupling
on treatment with benzyltriethylammonium tetrathiomolybdate 1 under very
mild conditions to give the corresponding diselenides in very good
yields.
A catalyst and additive‐free strategy for selectivering‐openingselenocyanation of saturated heterocycles with elementalselenium and TMSCN is developed, affording a series of aliphatic selenocyanates and selenaheterocycles. In the case of unprotected unstrained N‐heterocycles, the reactions offer ammonium selenonitriles that prove to be an efficient selenonitrile reagent.
A convenient, transition metal-free synthesis of difluoromethyl selenoethers from organic selenocyanates and TMSCF2H
作者:Tao Dong、Jing Nie、Cheng-Pan Zhang
DOI:10.1016/j.tet.2018.08.001
日期:2018.9
for the synthesis of aryl or alkyl difluoromethyl selenides (RSeCF2H) from the corresponding selenocyanates (RSeCN) and TMSCF2H/t-BuOK is described. The reaction performed in THF at 0 °C for 24 h or at room temperature for 6 h supplied a series of RSeCF2H in good to high yields. The successful preparation of difluoromethylselenolated sulfadimethoxine derivative and the scaled-up synthesis of 1-ben
描述了一种由相应的硒氰酸酯(RSeCN)和TMCSF 2 H / t -BuOK合成芳基或烷基二氟甲基硒化物(RSeCF 2 H)的有效且无过渡金属的方法。在THF中于0°C进行24小时或在室温下进行6小时的反应可提供一系列RSeCF 2H以高产到高产。例如,成功制备了二氟甲基硒化的磺基二甲恶英衍生物并按比例放大合成了1-苄基-5-((二氟甲基)硒基)二氢吲哚,表明该方法具有良好的实用性。该反应的优点包括温和的反应条件,良好的官能团耐受性,多种底物和高效率。该方案提供了许多新颖的二氟甲基硒醚,这些醚将加速此类化合物在生命科学领域的使用。