Design of novel chiral N,N,O-tridentate phenanthroline ligands and their application to enantioselective addition of organozinc reagents to aldehydes

Naganawa, Yuki; Namba, Tomoya; Aoyama, Tomotaka; Shoji, Kentaro; Nishiyama, Hisao

doi:10.1039/c4cc05020g

Cited by 34 publications

(16 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A mixed‐ligand complex containing the amino acid Schiff‐base and 1,10‐phenanthroline is an interesting system for researchers because of its applications in anticancer drugs, sensors, photophysics, and so on Preparation of water‐soluble complexes, owing to their higher compatibility with biosystems and less environmental contamination, has gained special importance. On the other hand, 1,10‐phenanthroline is known as an agent to design molecules due to the π‐stacking of the Phen rings …”

Section: Introductionmentioning

confidence: 99%

Water‐based synthesis of ZnO nanoparticles via decomposition of a ternary zinc complex containing Schiff‐base, chelating, and Phen ligands

Gharagozlou

Naghibi

Ataei

2018

J Chinese Chemical Soc

View full text Add to dashboard Cite

The recent environmental awareness has been the motivation for the growing preference for environmentally friendly and water‐based systems in chemical synthesis. In the present work, ZnO nanoparticles were synthesized via a novel method without any water‐insoluble compounds. At the first step, a binary Zn Schiff‐base complex was prepared from sodium salicylaldehyde‐5‐sulfonate, L‐alanine, and zinc acetate. Then, a ternary Zn complex containing the Schiff‐base, chelating, and Phen ligands was synthesized from the as‐synthesized binary Zn Schiff base and 1,10‐phenanthroline monohydrate. This intermediate product showed high water solubility and long‐term stability. Finally, ZnO nanoparticles were synthesized through the calcination of the ternary complex powder at 400, 500, and 600 °C. Combining X‐ray diffraction (XRD) and energy dispersive spectroscopy (EDS) results, it was concluded that the samples contained the ZnO phase without any impurity phases, but Fourier transform infrared (FTIR) spectra implied the presence of a remaining impurity. According to the XRD, FTIR, and photoluminescence (PL) analyses, the as‐synthesized samples differed in terms of the defect content and lattice strain. The sample calcined at 500 °C possessed the lowest defect content and lattice strain. Transmission electron microscopy (TEM) imaging revealed the formation of ZnO nanoparticles with particles sizes of <20, ~50, and ~100 nm for samples heat‐treated at the different temperatures.

show abstract

Section: Introductionmentioning

confidence: 99%

Water‐based synthesis of ZnO nanoparticles via decomposition of a ternary zinc complex containing Schiff‐base, chelating, and Phen ligands

Gharagozlou

Naghibi

Ataei

2018

J Chinese Chemical Soc

View full text Add to dashboard Cite

show abstract

“…We previously developed a novel axially chiral phenanthroline ligand BinThro (Binol‐derived phenanthroline; 8 ) and examined its activity in enantioselective organozinc addition to aldehydes (Figure 1). 8 1,10‐Phenanthroline (phen) is a classical N , N ‐chelating reagent and is used in various organic reactions 9. However, studies on the development of chiral ligands utilizing the phen motif have been very limited, probably due to the difficulty of introducing an effective chiral environment with its rigid and planar structure 10.…”

Section: Methodsmentioning

confidence: 99%

Construction of a Chiral Silicon Center by Rhodium‐Catalyzed Enantioselective Intramolecular Hydrosilylation

Naganawa

Namba

Kawagishi

et al. 2015

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

Rhodium-catalyzed enantioselective desymmetrizing intramolecular hydrosilylation of symmetrically disubstituted hydrosilanes is described. The original axially chiral phenanthroline ligand (S)-BinThro (Binol-derived phenanthroline) was found to work as an effective chiral catalyst for this transformation. A chiral silicon stereogenic center is one of the chiral motifs gaining much attention in asymmetric syntheses and the present protocol provides cyclic five-membered organosilanes incorporating chiral silicon centers with high enantioselectivities (up to 91 % ee). The putative active Rh(I) catalyst takes the form of an N,N,O-tridentate coordination complex, as determined by several complementary experiments.

show abstract

“…[4][5][6] The applications of these ligands in transition metal-mediated catalyses have also been the subject of considerable investigation. [7][8][9][10][11][12] Although some aspects of the chemistry of 4,5-diazafluoren-9one and 4,5-diazafluorene have been studied, little is known regarding the coordination chemistry of these ligands, which are closely related to phenanthroline and bipyridines. [13][14][15][16][17][18][19] Recently, a review on the coordination chemistry and applications of metal complexes of various 4,5-diazafluorenes in catalysis, photochemistry and photophysics as well as in bioinorganic chemistry was reported.…”

Section: Introductionmentioning

confidence: 99%

Transfer hydrogenation of aryl ketones with homogeneous ruthenium catalysts containing diazafluorene ligands

Baran

Durap

Aydemir

et al. 2016

Applied Organom Chemis

View full text Add to dashboard Cite

Novel cationic ruthenium(II) complexes bearing a 4,5‐diazafluorene unit and p‐cymene as ligands have been synthesised. The complexes were characterised based on elemental analysis and Fourier transform infrared and nuclear magnetic resonance spectroscopies. The synthesised Ru(II) complexes were employed as pre‐catalysts for the transfer hydrogenation of aromatic ketones using 2‐propanol as both hydrogen source and solvent in the presence of NaOH. All complexes showed high catalytic activity as catalysts in the reduction of substituted acetophenones to corresponding secondary alcohols. The products of catalysis were obtained with conversion rates of between 80 and 99%. Among the seven new complexes investigated, the most efficient catalyst showed turnover frequencies in the range 255–291 h−1 corresponding to 85 to 97% conversion, respectively. Copyright © 2016 John Wiley & Sons, Ltd.

show abstract

Design of novel chiral N,N,O-tridentate phenanthroline ligands and their application to enantioselective addition of organozinc reagents to aldehydes

Abstract: The novel N,N,O-tridentate phenanthroline ligand (BinThro) bearing an axially chiral binaphthyl backbone prepared from BINOL was found to be an effective chiral catalyst for enantioselective addition of diethylzinc to aromatic aldehydes with high enantioselectivity (up to 95% ee).

Cited by 34 publications

References 43 publications

Water‐based synthesis of ZnO nanoparticles via decomposition of a ternary zinc complex containing Schiff‐base, chelating, and Phen ligands

Water‐based synthesis of ZnO nanoparticles via decomposition of a ternary zinc complex containing Schiff‐base, chelating, and Phen ligands

Construction of a Chiral Silicon Center by Rhodium‐Catalyzed Enantioselective Intramolecular Hydrosilylation

Transfer hydrogenation of aryl ketones with homogeneous ruthenium catalysts containing diazafluorene ligands

Contact Info

Product

Resources

About