Enantioselective Hydrophosphination of Enones with Diphenylphosphine Catalyzed by Bis(imidazoline) NCN Pincer Palladium(II) Complexes
作者:Xin-Qi Hao、Yong-Wei Zhao、Jing-Jing Yang、Jun-Long Niu、Jun-Fang Gong、Mao-Ping Song
DOI:10.1021/om500144b
日期:2014.4.14
chiral NCN pincer Pd(II) complexes with 1,3-bis(2′-imidazolinyl)phenyl (Phebim) ligands were synthesized via the C–H activation or oxidative addition method. A dinuclear macrocyclic Pd(II) complex was also prepared by reaction of the Phebim-H ligand with PdCl2. All of the new compounds were fully characterized, and X-ray single-crystal structures were obtained for two of the complexes. The Pd(II) complexes
The first highly enantioselective catalytic synthesis of P-stereogenic secondary phosphine-boranes was realized by the asymmetric addition of primary phosphine to electron-deficient alkenes with a newly developed unsymmetric bisphosphine (PCP′) pincer-nickel complex. Various P-stereogenic secondary phosphine-boranes were obtained in 57–92% yields with up to 99% ee and >20:1 dr. The follow-up alkylation
Unsymmetrical Chiral PCN Pincer Palladium(II) and Nickel(II) Complexes with Aryl-Based Aminophosphine–Imidazoline Ligands: Synthesis via Aryl C–H Activation and Asymmetric Addition of Diarylphosphines to Enones
作者:Ming-Jun Yang、Yan-Jing Liu、Jun-Fang Gong、Mao-Ping Song
DOI:10.1021/om200350h
日期:2011.7.25
distorted-square-planar geometry. The potential of the obtained chiral pincers in the asymmetricaddition of diarylphosphines to β-substituted enones or trans-β-nitrostyrene was investigated. The Pd pincer 4c, the chirality of which originated from l-phenylglycinol, was found to be an effective catalyst for the asymmetricaddition of diphenylphosphine to a series of β-aryl enones with high enantioselectivities
通过将市售3-硝基苯甲酸中的羧基和硝基分别转化为手性咪唑啉和胺,可以轻松合成手性3-(2'-咪唑啉基)苯胺3a – c。的3-(2'-咪唑啉基)一锅磷酸/金属化反应的苯胺图3a - Ç,其中在氨基3A - Ç物首先通过与PPH反应磷酸化2氯,接着金属化用的PdCl 2或无水的NiCl 2原位提供了三种不对称的手性PCN钳形Pd(II)配合物4a – c和Ni(II)配合物5a与芳基氨基膦-咪唑啉配体通过相关配体的芳基C–H键活化作用。所有新化合物均通过元素分析(配体前体的HRMS),1 H和13 C NMR,31 P 1 H} NMR(用于钳形配合物)和IR光谱进行了表征。Pd络合物4a,c和Ni络合物5a的分子结构已经通过X射线单晶衍射确定。每个复合体均采用典型的扭曲正方形平面几何形状。研究了所获得的手性钳在将二芳基膦不对称加成到β-取代的烯酮或反式-β-硝基苯乙烯中的潜力。钯钳4c
Chiral Palladacycles with N-Heterocyclic Carbene Ligands as Catalysts for Asymmetric Hydrophosphination
作者:Sara Sabater、Jose A. Mata、Eduardo Peris
DOI:10.1021/om400007a
日期:2013.2.25
Design of chiral palladacycles with N-heterocycliccarbene (NHC) ligands has been carried out in good yields starting form commercially available enantiopure benzylamines. The methodology developed consists of the formation of palladium dimers with orthometalated benzylamines. The dimers undergo facile chloride-bridge-splitting with azolium salts under basic conditions to afford the chiral palladacycles
Versatile Syntheses of Optically Pure PCE Pincer Ligands: Facile Modifications of the Pendant Arms and Ligand Backbones
作者:Xiang-Yuan Yang、Wee Shan Tay、Yongxin Li、Sumod A. Pullarkat、Pak-Hing Leung
DOI:10.1021/acs.organomet.5b00132
日期:2015.4.27
one-pot synthetic procedure was used efficiently to prepare the corresponding optically pure pincer complexes. All the new complexes were characterized by NMR and mass spectroscopy. The molecular structures of several selected complexes have also been elucidated by X-ray crystallography. Preliminary studies indicated that minor structural changes on these novel pincer complexes affect their chemical