Recyclable and highly active cationic 2,2′-bipyridyl palladium(II) catalyst for Suzuki cross-coupling reaction in water
作者:Wei-Yi Wu、Shao-Nung Chen、Fu-Yu Tsai
DOI:10.1016/j.tetlet.2006.10.127
日期:2006.12
A water-soluble and air-stable palladium(II)/cationic 2,2′-bipyridyl catalyst is proven to be a recyclable and extremely active catalyst for Suzuki reaction in aqueous and aerobic conditions. The conveniently prepared catalyst showed little loss in the catalytic process of the coupling between 4-bromoacetophenone and phenylboronic acid after five cycles. For the reactions of aryl chlorides, biaryls
One-Carbon Oxidative Annulations of 1,3-Enynes by Catalytic C−H Functionalization and 1,4-Rhodium(III) Migration
作者:Johnathon D. Dooley、Hon Wai Lam
DOI:10.1002/chem.201706043
日期:2018.3.15
Rhodium(III)‐catalyzed C−H functionalization‐oxidativeannulations of aromatic substrates with 1,3‐enynes that contain allylic hydrogen atoms cis to the alkyne are described. The key step in these reactions is an alkenyl‐to‐allyl 1,4‐rhodium(III) migration to give electrophilic π‐allylrhodium(III) species. Nucleophilic trapping of these species gives heterocycles such as benzopyrans, isobenzofuranones
Benzimidazolium-Pyrazole-Palladium(II) Complexes: New and Efficient Catalysts for Suzuki, Heck and Sonogashira Reactions
作者:Fuwei Li、T. S. Andy Hor
DOI:10.1002/adsc.200800356
日期:2008.10.6
through N⋅⋅⋅HO and OH⋅⋅⋅O bonding. These hybrid ligands add to palladium(II) to give high yields of air-stable complexes that are fully characterized by NMR, ESI, and X-ray single-crystal crystallography. They are active Suzuki catalysts at roomtemperature towards cross-coupling of unactivated aryl bromides and 5- or 6-membered heteroaryl bromides with arylboronicacids with turnover frequencies (TOF)
已经方便地制备了三种不对称的苯并咪唑-吡唑NN配体2-(1-丙基苯并咪唑基甲基)-3,5-二-R-吡唑(R = H,Me,t- Bu)并对其结构进行了分析。R = Me化合物在223 K处的固体晶格堆积显示出一维“ Z字形”水链,该水链通过N⋅⋅⋅HO和OH⋅⋅⋅O键被有机分子通道稳定化。这些杂化的配体加到钯(II)中,从而获得高收率的空气稳定复合物,该复合物已通过NMR,ESI和X射线单晶晶体学进行了全面表征。它们是室温下的活性Suzuki催化剂,可将未活化的芳基溴化物和5或6元杂芳基溴化物与芳基硼酸交叉偶联,其周转频率(TOF)高达60,000 h -1。它们的催化效率明显优于CN卡宾-咪唑类似物。这些催化剂在芳基溴化物的Heck和Sonogashira交叉偶联反应中也有活性,以高收率得到所需产物。这些结果表明,这些Pd(II)与N基杂化配体的配合物是适用于有氧条件下不同类型的交叉偶联反应的通用且有效的催化剂。
Synthesis of Dibenzopyranones through Palladium-Catalyzed Directed C-H Activation/Carbonylation of 2-Arylphenols
作者:Shuang Luo、Fei-Xian Luo、Xi-Sha Zhang、Zhang-Jie Shi
DOI:10.1002/anie.201304295
日期:2013.9.27
Dibenzopyranones were synthesized by a palladium‐catalyzed phenol‐directed C–H activation/carbonylation of 2‐phenylphenol derivatives in the presence of CO. Pd(OAc)2 was used as a catalyst and Cu(OAc)2 as a catalytic oxidant in the presence of air.
Copper-catalyzed oxidative aromatization of 2-cyclohexen-1-ones to phenols in the presence of catalytic hydrogen bromide under molecular oxygen
作者:Kotaro Kikushima、Yuta Nishina
DOI:10.1039/c3ra43071e
日期:——
Catalytic oxidative aromatization has been achieved using 2-cyclohexen-1-ones to obtain phenol derivatives in the presence of a catalytic amount of copper salt and aqueous HBr under molecular oxygen. The amount of HBr was successfully reduced to a catalytic quantity, and the other additive such as a ligand and an oxidant as well as inert conditions were unnecessary. Various mono-, di-, and trisubstituted