Disclosed herein are improved methods for the synthesis of honokiol, as well as methods for the synthesis of 3,3′-di-tert-butyl-5,5′-dimethyl-[1,1′-biphenyl]-2,4′-diol, 3′,5-dimethyl-[1,1′-biphenyl]-2,4′-diol, and 2,4′-dimethoxy-3′,5-dimethyl-1,1′-biphenyl, 3,3′,5,5′-tetra-tert-butyl-[1,1′-biphenyl]-2,4′-diol, and certain tetrasubstituted bisphenols, and uses therefor.
to acting as a base during the catalytic process. In the catalyticsystem with a strong base, the soluble active PdII ion exhibited anti-reduction properties, which prevented aggregation and deactivation of Pd species. The entire catalyticsystem could be recycled after separating the product by simple filtration. The water-compatible and air-stable effective catalytic protocol described herein represents
Robust and Electron-Rich<i>cis</i>-Palladium(II) Complexes with Phosphine and Carbene Ligands as Catalytic Precursors in Suzuki Coupling Reactions
作者:Chuang-Yi Liao、Kai-Ting Chan、Cheng-Yi Tu、Yu-Wei Chang、Ching-Han Hu、Hon Man Lee
DOI:10.1002/chem.200801296
日期:2009.1.2
A new imidazolinium ligand precursor [L2H]Cl (2) was prepared in 86 % yield. Compared with its imidazolium counterpart, [L1H]Cl (1), 2 is very sensitive to moisture and can undergo ring‐opening reactions very readily. Palladium complexes with the ring‐opened productsfromimidazolinium salts were isolated and characterized by X‐ray crystallography. Theoretical studies confirmed that the imidazolinium
以86%的收率制备了新的咪唑啉鎓配体前体[L 2 H] Cl(2)。与它的咪唑鎓对应物[L 1 H] Cl(1)相比,2对水分非常敏感,并且很容易发生开环反应。分离了具有咪唑啉鎓盐的开环产物的钯配合物,并通过X射线晶体学对其进行了表征。理论研究证实,咪唑啉盐比咪唑鎓盐具有更高的开环反应倾向。新的膦/卡宾钯混合复合物,顺式[PdCl 2(L)(PR 3)](L = L 1和L 2; R = Ph,Cy)已成功制备。可变温度NMR光谱研究和热重分析表明,这些配合物具有很高的鲁棒性。在不同的卡宾基团上的新配合物的结构和电子性质(咪唑-2-亚基(不饱和卡宾)与咪唑啉-2-亚基(饱和卡宾))和膦基(PPh 3与PCy 3)为通过X射线晶体学,X射线光电子能谱和理论计算进行了详细研究。催化研究表明,顺式-[PdCl 2(L 2)(PCy 3)]是合格的Pd II 铃木偶联反应的前催化剂,其中不活泼的芳基氯可用作底物。
Electrochemical Synthesis of Biaryls via Oxidative Intramolecular Coupling of Tetra(hetero)arylborates
作者:Arif Music、Andreas N. Baumann、Philipp Spieß、Allan Plantefol、Thomas C. Jagau、Dorian Didier
DOI:10.1021/jacs.9b12300
日期:2020.3.4
scope, scalability and robustness of this unconventional catalyst-free transformation, leading to functional-ized biaryls and ultimately furnishing drug-like small molecules as well as late stage derivatization of natural compounds. In addition, the observed selectivity of the oxidative coupling reaction is related to the electronic structure of the TABs through quantum-chemical calculations and experimental
Sublimable bis( β -iminoenolate)palladium(II) complexes and their application as catalysts in Suzuki-Miyaura reactions
作者:Mi Jin Kim、Myung Jin Jung、Yeong Joon Kim、Ha Kyoung Sung、Ju Young Lee、Sung Jin Ham、Chan Pil Park
DOI:10.1016/j.tetlet.2018.06.051
日期:2018.8
The Pd(II) complexes strongly chelated by two β-iminoenolate ligands were easily synthesized in only two steps, and purified based on their sublimable and highly stable property. The Pd(II) complexes anchored on a silica surface showed good catalytic activity in Suzuki-Miyaurareactions (up to 99% yield with 0.05 mol% catalyst). They tolerated a wide range of temperature (rt∼110 °C) and various solvents