“Inverse” Frustrated Lewis Pairs: An Inverse FLP Approach to the Catalytic Metal Free Hydrogenation of Ketones
作者:Suresh Mummadi、Amandeep Brar、Guoqiang Wang、Dustin Kenefake、Rony Diaz、Daniel K. Unruh、Shuhua Li、Clemens Krempner
DOI:10.1002/chem.201804370
日期:2018.11.7
For the first time have boron‐containing weak Lewis acids been demonstrated to be active components of Frustrated LewisPair (FLP) catalysts in the hydrogenation of ketones to alcohols. Combining the organosuperbase (pyrr)3P=NtBu with the Lewis acid 9‐(4‐CF3‐C6H4)‐BBN generated an “inverse” FLP catalyst capable of hydrogenating a range of aliphatic and aromatic ketones including N‐, O‐ and S‐functionalized
含硼的弱路易斯酸首次被证明是酮加氢成醇时的沮丧路易斯对(FLP)催化剂的活性组分。将有机超强碱(pyrr)3 P = N t Bu与路易斯酸9-(4-CF 3 - C 6 H 4)-BBN结合产生一种“逆向” FLP催化剂,该催化剂能够加氢包括N在内的一系列脂族和芳族酮,O和S功能化的底物以及生物质衍生的乙酰丙酸乙酯。初步的计算和实验研究表明,使用“逆” FLP进行催化氢化的机理不同于包含强路易斯酸(例如B(C 6 F 5))的常规FLP催化剂。)3。
Metal-ligand cooperativity in a ruthenium(II) complex of bis-azoaromatic ligand for catalytic dehydrogenation of alcohols
Abstract Herein a new Ru-phosphine complex (1) with molecular formula [RuL(PPh3)Cl2] is reported where L is a redox active pincer ligand 2,6-bis(phenylazo)pyridine. The isolated complex has been characterized by usual spectroscopic techniques including single crystal X-ray crystallographic analysis. Complex 1 efficiently catalyzes aerobic oxidation of a wide range of primary and secondary benzylic
A Well-Defined Monomeric Aluminum Complex as an Efficient and General Catalyst in the Meerwein-Ponndorf-Verley Reduction
作者:Brian McNerney、Bruce Whittlesey、David B. Cordes、Clemens Krempner
DOI:10.1002/chem.201404994
日期:2014.11.10
sustainable reduction of aldehydes and ketones but has not found widespread application in organic synthesis due to the high catalyst loading often required to obtain satisfactory yields of the reduced product. We report here on the synthesis and structure of a sterically extremely overloaded siloxide‐supported aluminum isopropoxide capable of catalytically reducing a wide range of aldehydes and ketones (52
Mild sp<sup>2</sup>Carbon–Oxygen Bond Activation by an Isolable Ruthenium(II) Bis(dinitrogen) Complex: Experiment and Theory
作者:Samantha Lau、Bryan Ward、Xueer Zhou、Andrew J. P. White、Ian J. Casely、Stuart A. Macgregor、Mark R. Crimmin
DOI:10.1021/acs.organomet.7b00632
日期:2017.9.25
bis(dinitrogen) complex [Ru(H)2(N2)2(PCy3)2] (1) reacts with aryl ethers (Ar–OR, R = Me and Ar) containing a ketone directing group to effect sp2C–O bondactivation at temperatures below 40 °C. DFT studies support a low-energy Ru(II)/Ru(IV) pathway for C–O bondactivation: oxidative addition of the C–O bond to Ru(II) occurs in an asynchronous manner with Ru–C bond formation preceding C–O bond breaking. Alternative
Substituierte Imidazole der allgemeinen Formel
oder deren Salze, worin Ph unsubstituiertes oder durch Niederalkyl oder Niederalkoxy substituiertes Phenyl bedeutet und R1 und R2 jeweils Niederalkyl bedeuten, Verfahren zu ihrer Herstellung, ihre Verwendung sowie pharmazeutische Präparate.
Die Verbindungen der Formel I weisen beispielseise antidepressive Eigenschaften auf.
通式如下的取代咪唑
或其盐类,其中 Ph 是未被取代或被低级烷基或低级烷氧基取代的苯基,R1 和 R2 分别是低级烷基,它们的制备工艺、用途和药物制剂。
例如,式 I 的化合物具有抗抑郁特性。