Iridium‐Catalysed Reductive Deoxygenation of Ketones with Formic Acid as Traceless Hydride Donor
作者:Zhiheng Yang、Xueya Zhu、Shiyi Yang、Weiyan Cheng、Xiaojian Zhang、Zhanhui Yang
DOI:10.1002/adsc.202000821
日期:2020.12.8
An iridium‐catalysed deoxygenation of ketones and aldehydes is achieved, with formic acid as hydride donor and water as co‐solvent. At low catalyst loading, a number of 4‐(N,N‐disubstituted amino) arylketones are readily deoxygenated in excellent yields and chemoselectivity. Numerous functional groups, especially phenolic and alcoholic hydroxyls, secondary amine, carboxylic acid, and alkyl chloride
以甲酸为氢化物供体,水为助溶剂,实现了铱催化的酮和醛的脱氧。在低催化剂负载下,许多4-(N,N-二取代氨基)芳基酮易于脱氧,具有出色的收率和化学选择性。许多官能团,尤其是酚羟基和醇羟基,仲胺,羧酸和烷基氯,都具有良好的耐受性。当使用DCO 2 D和D 2 O代替它们的氢化对应物时,可获得双歧化的双链烷烃达90%。激活4‐(N,N已证明二取代氨基)芳基会经历各种有用的转化。脱氧氘已用于制备氘代药物分子Chlorambucil-4,4- d 2。
Acylboronates in Polarity-Reversed Generation of Acyl Palladium(II) Intermediates
作者:Alina Trofimova、Aleksandra Holownia、Chieh-Hung Tien、Martynas J. Širvinskas、Andrei K. Yudin
DOI:10.1021/acs.orglett.1c00742
日期:2021.5.7
process between aryl (pseudo)halides and boron-based acyl anion equivalents. This mode of acylboronate reactivity represents polarity reversal, which is supported by the observation of tetracoordinated boronate and acyl palladium(II) species by 11B, 31P NMR, and massspectrometry. A broad scope of aliphatic and aromatic acylboronates has been examined, as well as a variety of aryl (pseudo)halides.
我们报告芳基(假)卤化物和硼基酰基阴离子当量之间的催化交叉偶联过程。酰基硼酸酯反应性的这种模式表示极性反转,这通过11 B,31 P NMR和质谱观察到四配位的硼酸酯和酰基钯(II)物种得到支持。已经研究了广泛范围的脂族和芳族酰基硼酸酯,以及各种芳基(假)卤化物。
Evolution of Concise and Flexible Synthetic Strategies for Trichostatic Acid and the Potent Histone Deacetylase Inhibitor Trichostatin A
作者:Casey C. Cosner、Vijaya Bhaskara Reddy Iska、Anamitra Chatterjee、John T. Markiewicz、Steven J. Corden、Joakim Löfstedt、Tobias Ankner、Joshua Richer、Tyler Hulett、Douglas J. Schauer、Olaf Wiest、Paul Helquist
DOI:10.1002/ejoc.201201233
日期:2013.1
enantioenriched forms. Three independent synthetic pathways were developed with varying degrees of efficiency and convergency. In the first synthesis, the key step was a vinylogous Horner-Wadsworth-Emmons condensation. A Marshall propargylation reaction was used as the key step in the second synthesis, and Pd-catalyzed a-alkenylation of a ketone zinc enolate by using various functionalized alkenyl or
Catalytic Cross-Coupling Reaction of Esters with Organoboron Compounds and Decarbonylative Reduction of Esters with HCOONH<sub>4</sub>: A New Route to Acyl Transition Metal Complexes through the Cleavage of Acyl−Oxygen Bonds in Esters
ketones. Acyl−alkyl coupling to dialkyl ketones is also achieved by the use of 9-alkyl-9-BBN in place of boronates. The Ru3(CO)12-catalyzed decarbonylative reduction of esters with ammonium formate (HCOONH4) leading to hydrocarbons is also described. No expected aldehydes are produced, and controlled experiments indicate that aldehydes are not intermediate for the transformation. A hydrosilane can also be