The highlyselective anti‐Markovnikov addition of thiols to unactivated alkenes and alkynes was demonstrated by using 3,4‐dimethyl‐5‐vinylthiazolium iodide or its polymer, poly(3,4‐dimethyl‐5‐vinylthiazolium) iodide, as a complementary catalyst. The reaction proceeded cleanly under base‐free conditions in air with both aromatic and aliphatic thiols. The polymer catalyst showed a high turnover number
Scandium(III) triflate promoted highly selective addition of thiols to functionalizedolefins under mild conditions. The addition follows anti-Markovnikov regioselectivities, which are unusual for Lewis acids-catalyzed hydrothiolation. This reaction marks broad functional groups tolerance, which opens a beneficial synthetic route to functionalized and biologically active thio-compounds. This method
Visible light photocatalysis with benzophenone for radical thiol-ene reactions
作者:Manjula Singh、Arvind K. Yadav、Lal Dhar S. Yadav、R.K.P. Singh
DOI:10.1016/j.tetlet.2017.04.060
日期:2017.6
for an anti-Markovnikov hydrothiolation of unactivated olefins using benzophenone as an inexpensive photocatalyst at room temperature. Anti-Markovnikov adducts of a wide variety of olefins and thiols are formed in highly regioselective manner and good to excellent yields. The present radical thiol-ene reaction is operationally simple and well tolerates a variety of functional groups.
Thiol-Ene “Click” Reaction Triggered by Neutral Ionic Liquid: The “Ambiphilic” Character of [hmim]Br in the Regioselective Nucleophilic Hydrothiolation
作者:Rajesh Kumar、Saima、Amit Shard、Nitin H. Andhare、Richa、Arun K. Sinha
DOI:10.1002/anie.201408721
日期:2015.1.12
the “ambiphilic” character of the ionicliquid promotes the nucleophilic addition of thiol to styrene through an anti‐Markovnikov pathway. The catalyst recyclability and the extension of the methodology for thiol–yne click chemistry are additional benefits. A competitive study among thiophenol, styrene, and phenyl acetylene revealed that the rate of reaction is in the order of thiol–yne>thiol–ene>dimerization
硫醇-“咔嗒”化学已成为构建碳-杂原子(CS)键的有力策略,通常会形成两个区域异构体。为此,已经探索了中性离子液体[hmim] Br作为溶剂兼催化剂,用于从活化和失活的苯乙烯衍生物或仲苄醇和硫醇合成线性硫醚,而无需使用金属络合物,碱或自由基引发剂。此外,使用1进行详细的机械研究1 H NMR光谱和四极杆飞行时间电喷雾电离质谱(Q-TOF ESI-MS)表明,离子液体的“两亲”特性通过反马尔可夫尼科夫途径促进了巯基与苯乙烯的亲核加成。催化剂的可回收性和硫醇-炔点击化学方法的扩展是其他好处。硫酚,苯乙烯和苯基乙炔之间的竞争研究表明,反应速率为[hmim] Br中的硫醇-炔>硫醇-烯>硫醇二聚的顺序。
Transition‐Metal‐Free Reduction of
<i>α</i>
‐Keto Thioesters with Hydrosilanes at Room Temperature: Divergent Synthesis through Reagent‐Controlled Chemoselectivities
作者:Rajib Maity、Bhanuranjan Das、Indrajit Das
DOI:10.1002/adsc.201900222
日期:2019.5.14
acid as a promoter can be used for the reagent‐controlled chemoselective reduction at room temperature of conjugated C=C bond, enone moiety, or the carbonyl of (β,γ‐unsaturated) α‐keto thioesters, providing facile access to β,γ‐saturatedα‐keto thioesters, α‐hydroxy thioesters, or silyl ethers. The reaction pathway and the chemoselectivity can be fine‐tuned through the judicious choice of the hydrosilane
氢硅烷与布朗斯台德酸或路易斯酸作为促进剂的组合可用于在室温下进行试剂控制的化学选择还原反应,以还原共轭C = C键,烯酮部分或(β,γ-不饱和)α-酮的羰基硫酯,可轻松获得β,γ-饱和的α-酮硫代酯,α-羟基硫代酯或甲硅烷基醚。可以通过明智地选择氢化硅烷或反应条件来微调反应途径和化学选择性。该反应可耐受包括不稳定的硫酯在内的各种官能团,并且通常以中等至极好的收率获得产物。不对称硫醚也可以使用PMHS和催化性B(C 6 F 5)3合成通过两个羰基的还原性脱氧。β,γ-不饱和α-羟基硫代酯和β,γ-饱和α-酮硫代酯的饱和α-酮酰胺的胺介导和无偶联剂的合成突出了其适用性。