光氧化还原催化通常依赖于使用单个发色团,而将两种不同的光吸收剂组合在一起的策略很少见。在绿色植物的光系统 I 和 II 中,两个独立的发色团 P 680和 P 700都相互独立地吸收光,然后它们的激发能量在所谓的 Z 方案中组合,以驱动热力学上的整体反应非常严格。在这里,我们采用这个概念在有机基材上进行光氧化还原反应,其中两个红色光子的组合能量输入而不是蓝色或紫外光。具体来说,Cu I双(α-二亚胺)配合物与原位结合在过量的二异丙基乙胺催化下形成 9,10-二氰基蒽自由基阴离子。50 次脱卤和脱甲苯基反应。这种双重光氧化还原方法似乎很有用,因为红光的破坏性较小,并且比蓝光或紫外线辐射具有更大的穿透深度。紫外-可见瞬态吸收光谱表明,溶剂从乙腈到丙酮的细微变化会引起反应机制的转变,包括主要的光诱导电子转移或主要的三重态-三重态能量转移途径。我们的研究说明了在多光子激发条件下运行的系统的机械复杂
Unusual Reaction of Azoxybenzenes with<i>p</i>-Toluenesulfonic Acid in Acetic Anhydride
作者:Ichiro Shimao、Ken Fujimori、Shigeru Oae
DOI:10.1246/bcsj.55.1538
日期:1982.5
azoxybenzene with p-toluenesulfonic acid in aceticanhydride gave tosylates of 4- and 2-(phenylazo)phenols, and the corresponding acetates as by-product, besides azobenzene. However, a similar reaction of 4,4′-difluoroazoxybenzene gave 2-tosyloxy-4,4′-difluoroazobenzene as rearrangement product, besides 4-fluorophenyl tosylate and 4-fluorophenyl acetate. Meanwhile, the reaction of 4,4′-diacetoxyazoxybenzene
Single-Component Phosphinous Acid Ruthenium(II) Catalysts for Versatile C−H Activation by Metal-Ligand Cooperation
作者:Daniel Zell、Svenja Warratz、Dmitri Gelman、Simon J. Garden、Lutz Ackermann
DOI:10.1002/chem.201504851
日期:2016.1.22
Well‐defined ruthenium(II) phosphinousacid (PA) complexes enabled chemo‐, site‐, and diastereoselective C−H functionalization of arenes and alkenes with ample scope. The outstanding catalytic activity was reflected by catalyst loadings as low as 0.75 mol %, and the most step‐economical access reported to date to angiotensin II receptor antagonist blockbuster drugs. Mechanistic studies indicated a
A novel Ni0‐catalyzed carboxylation of aryl tosylates with carbon dioxide has been achieved under moderate temperatures and atmospheric pressure. In this procedure, the active Ni0 species is generated in situ by simply mixing the Ni0 precatalyst [NiBr2(bipy)] with an excess of manganese metal. This approach requires neither a glove‐box nor the tedious preparation of sophisticated intermediate organometallic
FUNCTIONALIZED MAGNETIC NANOPARTICLE, A CATALYST, A METHOD FOR FORMING C-C BONDS
申请人:KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS
公开号:US20180099987A1
公开(公告)日:2018-04-12
A functionalized magnetic nanoparticle including an organometallic sandwich compound and a magnetic metal oxide. The functionalized magnetic nanoparticle may be reacted with a metal precursor to form a catalyst for various C—C bond forming reactions. The catalyst may be recovered with ease by attracting the catalyst with a magnet.
Iron-Catalyzed Cross-Coupling Reactions of Arylmagnesium Reagents with Aryl Chlorides and Tosylates: Influence of Ligand Structural Parameters and Identification of a General N-Heterocyclic Carbene Ligand
作者:Wenqin Wu、Qiaoqiao Teng、Yi-Yuan Chua、Han Vinh Huynh、Hung A. Duong
DOI:10.1021/acs.organomet.7b00180
日期:2017.6.26
evaluation of N-heterocyclic carbene ligands in the iron-catalyzed cross-coupling reactions of arylchlorides and arylmagnesium reagents is performed. There is no clear correlation between the donor strength of the N-heterocyclic carbene and the reaction outcome. Instead, the highest yields of the desired biaryl product are obtained with sterically demanding ligands possessing large %Vbur values. Through