Promoting Effect of Crystal Water Leading to Catalyst-Free Synthesis of Heteroaryl Thioether from Heteroaryl Chloride, Sodium Thiosulfate Pentahydrate, and Alcohol
作者:Xiantao Ma、Jing Yu、Ran Yan、Mengli Yan、Qing Xu
DOI:10.1021/acs.joc.9b01670
日期:2019.9.6
can promote its multicomponent reaction with heteroaryl chlorides and alcohols, providing a facile, green, and specific synthesis of unsymmetrical heteroaryl thioethers via one-step formation of two C–S bonds under catalyst-, additive-, and solvent-free conditions. Mechanistic studies suggest that the crystal water in Na2S2O3·5H2O is crucial in generating the key thiol intermediates and byproduct NaHSO4
观察到五水硫代硫酸钠(Na 2 S 2 O 3 ·5H 2 O)中的结晶水可以促进其与杂芳基氯化物和醇类的多组分反应,从而一步一步提供了一种不对称的杂芳基硫醚的简便,绿色且特异的合成方法在无催化剂,无添加剂和无溶剂的条件下形成两个C–S键。机理研究表明,Na 2 S 2 O 3 ·5H 2 O中的结晶水对于生成关键的硫醇中间体和副产物NaHSO 4至关重要,后者可以催化醇被硫醇的脱水取代,从而制得硫醚。
Efficient Generation of C-S Bonds<i>via</i>a By-Product-Promoted Selective Coupling of Alcohols, Organic Halides, and Thiourea
alcohols, heteroaryl halides, and thiourea has been developed for direct and selective synthesis of heteroaryl thioethers. This method can be easily scaled up to the gram scale and extended to dialkyl thioethers, heteroaryl selenides, benzothiazoles, and some antimycobacterially‐active thioethers. Mechanisticstudies revealed that a by‐product‐promoted in situ C–O activation of alcohols to more reactive
Utilizing 2‐phenylpropanal as coupling partner for C‐S bond formation via sequential thioarylation and decarbonylation process: A novel strategy for the synthesis of aryl alkyl sulfides
to aryl alkyl sulfides employing 2‐phenylpropanal as coupling partner is reported. Diaryl disulfides react with this aldehyde in the presence of morpholine and produce the corresponding sulfide products in high yields. In another part, disulfides are in situ generated in the reaction mixture fromaryl halides/CuI/Cyanodithioformate and coupled with 2‐phenylpropanal to access aryl alkyl sulfides.
在这项研究中,首次报道了使用2-苯基丙醛作为偶联伙伴直接接触芳基烷基硫化物。二芳基二硫化物在吗啉存在下与该醛反应,并以高收率生产相应的硫化物产物。在另一部分中,由芳基卤化物/ CuI /氰基二硫代甲酸酯在反应混合物中原位生成二硫化物,并与2-苯基丙醛偶合以生成芳基烷基硫化物。
Palladium and copper co-catalyzed Markovnikov hydrothiolation of terminal olefins and alkynes
A simple and efficient method for palladium and copper co-catalyzed Markovnikov hydrothiolation of thiols to olefins or alkynes has been developed. The reaction allows olefins or alkynes bearing various functional groups to react with different thiols, providing good to excellent yields of alkyl sulfides or vinyl sulfides. A proposed mechanistic study indicated that Cu(II) plays a key role in obtaining