Selectively esterified: Primary alcohols react with dioxygen as a benign oxidant in a palladium‐catalyzed oxidativeesterification (see scheme). The corresponding aldehydes and esters are formed highly selectively depending on the catalyst system. The reactions take place in the presence of commercially available ligands without the need for additional organic hydrogen acceptors.
Synthesis of Unsymmetrical <i>N</i>-Heterocyclic Carbene–Nitrogen–Phosphine Chelated Ruthenium(II) Complexes and Their Reactivity in Acceptorless Dehydrogenative Coupling of Alcohols to Esters
dehydrogenative coupling of alcohols to esters, and the excellent isolated yields of esters were given in a catalyst loading of 1% for para- and meta-substituted benzyl alcohols and long-chain primary alcohols. Although some ortho-substituted benzyl alcohols displayed a relatively low reactivity due to the steric hindrance and the coordination of electron donor with the ruthenium center, the good product
两种新型的钌络合物期RuH(CO)氯(PPH 3)(κ 2 -CP)(1)和[ FAC -RuH(CO)(PPH 3)(κ 3 -CNP)]氯(2)轴承不对称ñ -杂环合成了卡宾-氮-膦(CNP)并通过1 H NMR,31 P NMR和HRMS进行了表征。配合物2的结构通过单晶X射线衍射进一步确认。阴离子交换实验证明复合物2可以转化为复合物1在解决方案中。两种络合物在醇与酯的无受体脱氢偶联中显示出高催化性能,并且在对-和间-取代的苄醇和长链伯醇的催化剂负载量为1%时,酯的分离产率极佳。尽管由于空间位阻以及电子给体与钌中心的配位,一些邻位取代的苄醇显示出较低的反应性,但延长反应时间仍可获得良好的产物收率。特别地,该系统成功地实现了两种不同伯醇之间的酯的脱氢交叉偶联。
An environmentally benign solvent-free Tishchenko reaction
作者:Daniel C. Waddell、James Mack
DOI:10.1039/b810714a
日期:——
Herein, we describe the solvent-free ball milling Tishchenko reaction. Using high speed ball milling and a sodium hydride catalyst, the Tishchenko reaction was performed for aryl aldehydes in high yields in 0.5 hours. The reaction is not affected by the type of ball bearing used and can be successful when conducted in a liquid nitrogen environment.
Thorium complexes possessing expanded ring N-heterocyclic iminato ligands: synthesis and applications
作者:Tapas Ghatak、Shani Drucker、Natalia Fridman、Moris S. Eisen
DOI:10.1039/c7dt02126g
日期:——
Six and seven membered N-heterocyclic iminato ligands (L) are introduced allowing access a new class of Th(IV) complexes of the type Cp*2Th(L)(CH3). These complexes were studied in the Tishchenko reaction. Stoichiometric reactions together with kinetic and thermodynamic studies permit us to propose a plausible mechanism.
Synthesis, characterization and catalytic performances of benzimidazolin-2-iminato actinide (IV) complexes in the Tishchenko reactions for symmetrical and unsymmetrical esters
作者:Heng Liu、Maxim Khononov、Natalia Fridman、Matthias Tamm、Moris S. Eisen
DOI:10.1016/j.jorganchem.2017.09.020
日期:2018.2
benzimdazolin-2-iminato actinide−(IV) complexes [(Bim7-MeDipp/MeN)An(N(SiMe3)2)3] (An = U (3), Th (4)) and [(Bim4-MeDipp/MeN)An(N(SiMe3)2)3] (An = U (5), Th (6)) were synthesized and their solid state structures were established by single-crystal X-ray diffraction analysis. The catalytic performances of complexes 3–6 towards the homo- and cross-coupling of aldehydes (Tishchenko reaction) were studied and the thorium