Photoredox/Cobalt Dual‐Catalyzed Decarboxylative Elimination of Carboxylic Acids: Development and Mechanistic Insight
作者:Kaitie C. Cartwright、Ebbin Joseph、Chelsea G. Comadoll、Jon A. Tunge
DOI:10.1002/chem.202001952
日期:2020.9.25
Recently, dual‐catalytic strategies towards the decarboxylative elimination of carboxylicacids have gained attention. Our lab previously reported a photoredox/cobaloxime dual catalytic method that allows the synthesis of enamides and enecarbamates directly from N‐acyl amino acids and avoids the use of any stoichiometric reagents. Further development, detailed herein, has improved upon this transformation's
作者:Roshinee Costa、Natalie Barone、Christopher Gorczycka、Ernest F. Powers、William Cupelo、Joseph Lopez、Richard S. Herrick、Christopher J. Ziegler
DOI:10.1016/j.jorganchem.2009.02.024
日期:2009.6
We present the synthesis and characterization of a series of dioxime and pyridine-2-aldoxime complexes of rhenium(I) tricarbonyl. Complexes of the formula ReL(CO)3X (L = dioxime (1,2), dimethylglyoxime (3,4), diphenylglyoxime (5,6), 1,2-cyclohexanedione dioxime (7,8); X = Cl, Br) can be readily generated by reaction of the neutral ligand with Re(CO)5X (X = Cl, Br) or [Re(CO)3(H2O)3]Br. A similar set
我们介绍了synthesis(I)三羰基的一系列二肟和吡啶-2-醛肟配合物的合成和表征。配方的配合物ReL(一氧化碳)第三名X(L =二肟(1,2),二甲基乙二肟(3,4),diphenylglyoxime(5,6),1,2-环己二酮二肟(7,8); X =氯,溴)可通过以下的反应来容易地生成中性配体与回覆(一氧化碳)5X (X = Cl,Br)或 [回覆(一氧化碳)第三名(H2个Ø)第三名]溴。下式的一组类似的吡啶-2-醛肟ReL(一氧化碳)第三名X(L =吡啶-2-醛肟(9,10),2- pyridylamidoxime(11,12); X =氯,溴)也可以以类似的方式合成。化合物1 - 6,9和12是由单晶的X射线衍射特征的。这些络合物都表现出肟配体的双齿配位以及羰基在金属周围的预期面排列,卤化物完成了八面体配位球。肟基在所有配合物中均保持质子化。化合物1 - 12中从MLCT跃迁产生的紫外-可见区域的所有显示的吸收。
Merging Halogen-Atom Transfer (XAT) and Cobalt Catalysis to Override E2-Selectivity in the Elimination of Alkyl Halides: A Mild Route toward <i>contra</i>-Thermodynamic Olefins
作者:Huaibo Zhao、Alastair J. McMillan、Timothée Constantin、Rory C. Mykura、Fabio Juliá、Daniele Leonori
DOI:10.1021/jacs.1c06768
日期:2021.9.15
mechanistically distinct tactic to carry E2-type eliminations on alkyl halides. This strategy exploits the interplay of α-aminoalkyl radical-mediated halogen-atom transfer (XAT) with desaturative cobalt catalysis. The methodology is high-yielding, tolerates many functionalities, and was used to access industrially relevant materials. In contrast to thermal E2eliminations where unsymmetrical substrates give regioisomeric
Deprotection of Ketoximes Using Bismuth(III) Nitrate Pentahydrate
作者:Ram Mohan、Bryce Nattier、Kyle Eash
DOI:10.1055/s-2001-14568
日期:——
Ketoximes undergo facile deprotection in acetone-H20 (9: 1) in the presence 01' 0.5 equivalents of Bi(N03h·5H20. Bis muth(lII) nitrate is relatively non-toxic, insensitive to air and inex pensive. These features coupled with the use of a relatively non toxic solvent system make this method an attractive alternative to existing routes for deprotection of ketoximes.
Reactions of Cobaloxime Anions and/or Hydrides with Enynes as a New, General Route to 1,3- and 1,2-Dienylcobaloxime Complexes
作者:Heather L. Stokes、Mark E. Welker
DOI:10.1021/om960058f
日期:1996.5.28
A new method for the preparation of dienylcobaloxime complexes which involves reactions of cobaloxime anions and/or hydrides with enynes is reported. This new dienyl complex preparative method leads to cobalt-substituted 1,3- or 1,2-dienes depending on the enyne substitution pattern chosen. Subsequent Diels−Alder reactions of the 1,3-dienyl complexes and demetalation reactions of cobalt-substituted