Fe 3 O 4 @SiO 2 [电子邮件保护] II是通过二氧化硅包覆的磁性纳米颗粒,脲三唑和CoCl 2制备的。这种有机-无机杂化复合物,使用新戊酸酐,K 2 S 2 O 8和PPh 3作为导向基团,对游离酚和萘的区域选择性邻亚磺酰化表现出良好至优异的催化活性。分别用作氧化剂和添加剂。通过使用不同的技术(例如FT-IR,TGA,DTG,TEM,SEM,EDS,ICP和VSM分析)对新合成的催化剂进行了全面表征。与用于C H键活化和官能化的昂贵过渡金属相比,钴具有竞争力的价格,可及性和较低的毒性构成了该方法的宝贵优势。而且,这种多相催化剂可以在五个循环后被磁回收和再利用而不会显着损失其催化活性。
Nitrosonium ion catalysis: aerobic, metal-free cross-dehydrogenative carbon–heteroatom bond formation
作者:Luis Bering、Laura D’Ottavio、Giedre Sirvinskaite、Andrey P. Antonchick
DOI:10.1039/c8cc08328b
日期:——
coupling of heteroarenes with thiophenols and phenothiazines has been developed under mild and environmentally benign reaction conditions. For the first time, NOx+ was applied for catalytic C–S and C–N bond formation. A comprehensive scope for the C–H/S–H and C–H/N–H cross-dehydrogenative coupling was demonstrated with >60 examples. The sustainable cross-coupling conditions utilize ambient oxygen as the
杂芳烃与硫酚和吩噻嗪的催化交叉脱氢偶联已在温和且环境友好的反应条件下得到发展。首次将NO x +用于催化C–S和C–N键的形成。用60多个例子证明了C–H / S–H和C–H / N–H交叉脱氢偶联的综合范围。可持续的交叉偶联条件利用环境氧作为末端氧化剂,而水是唯一的副产物。
Direct C–H Thiolation for Selective Cross-Coupling of Arenes with Thiophenols via Aerobic Visible-Light Catalysis
An aerobic metal-free, visible-light-induced regioselective thiolation of phenols with thiophenols is reported. The cross-coupling protocol exhibits great functional group tolerance and high regioselectivity. Mechanistic studies reveal that the disulfide radical cation plays a crucial role in the visible-light catalysis of aerobic thiolation. Simply controlling the equivalent ratio of substrates enables
Iodine-catalyzed efficient 2-arylsulfanylphenol formation from thiols and cyclohexanones
作者:Yunfeng Liao、Pengcheng Jiang、Shanping Chen、Hongrui Qi、Guo-Jun Deng
DOI:10.1039/c3gc41671b
日期:——
A novel method for the formation of 2-arylsulfanylphenols fromthiols and cyclohexanones is described. Iodine was used as an effective catalyst for this kind of transformation. Cyclohexanones were used as a phenol source via a dehydrogenation and tautomerization reaction.
Co(II)-catalyzed regioselective clean and smooth synthesis of 2-(aryl/alkyl-thio)phenols via sp2 C H bond activation
作者:Abed Rostami、Vahid Khakyzadeh、Mohammad Ali Zolfigol、Amin Rostami
DOI:10.1016/j.mcat.2018.04.020
日期:2018.6
The first example of a smooth, practical and useful strategy for the preparation of ortho-aryl/alkyl sulfenyl phenols by using the reaction of aryl/alkyl thiols with phenols in the presence cobalt as catalyst, and with the assistance of acetic anhydride as directing group via CH bond activation, was developed. Described method enables to form selectively CS bond without any ligand, oxidant, and aryl/alkyl
Iodine-promoted 2-arylsulfanylphenol formation using cyclohexanones as phenol source
作者:Ya Chen、Fuhong Xiao、Hui Chen、Saiwen Liu、Guo-Jun Deng
DOI:10.1039/c4ra08014a
日期:——
A novel method for the formation of 2-arylsulfanylphenols using cyclohexanones as phenol source via dehydrogenation is described. Various aromatic sodium sulfinates and sulfonyl chlorides acted as efficient coupling partners to construct new C–S bonds in the presence of an iodine promoter.