BINOL Derivatives (binol + derivative)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Titanium(IV)/Tridentate BINOL Derivative as Catalyst for meso -Aziridine Ring-Opening Reactions: High Enantioselectivity, Strong Positive Non-Linear Effect and Structural Characterization

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1-2 2009
Rongmin Yu
Abstract A titanium-based chiral Lewis acid was found to be effective for the ring-opening reactions of meso -aziridines with aniline nucleophiles. The products were generally isolated in high yields and with high to excellent enantioselectivity. The catalytic system was studied by X-ray single crystal analysis. In experiments on non-linear effects a strong non-linear effect of the catalyst system was observed. [source]

Enantioselective Proteins: Selection, Binding Studies and Molecular Modeling of Antibodies with Affinity towards Hydrophobic BINOL Derivatives

CHEMBIOCHEM, Issue 16 2007
Brian Schou Rasmussen Dr.
Abstract In this paper, the initial steps towards the design of novel artificial metalloenzymes that exploit proteins as a second coordination sphere for traditional metal,ligand catalysis are described. Phage display was employed to select and study antibody fragments capable of recognizing hydrophobic BINOL derivatives designed to mimic BINAP, a widely used ligand in asymmetric metal-catalyzed reactions. The binding affinities of the selected antibodies towards a series of haptens were evaluated by using ELISA assays. A homology model of one of the most selective antibodies was constructed, and a computer-assisted ligand-docking study was carried out to elucidate the binding of the hapten. It was shown that, due to the hydrophobic nature of the haptens, a higher level of theoretical treatment was required to identify the correct binding modes. A small selection of the antibodies was found to discriminate between enantiomers and small structural modifications of the BINOL derivatives. The selectivities arise from hydrophobic interactions, and we propose that the identified set of antibodies provides a foundation for a novel route to artificial metalloenzymes. [source]

ChemInform Abstract: Enantioselective Addition of Diethylzinc to Aromatic Aldehydes Catalyzed by Ti(IV) Complexes of C2 -Symmetrical Chiral BINOL Derivatives.

CHEMINFORM, Issue 17 2009
Shaohua Gou
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

ChemInform Abstract: Bifunctional Enantioselective Ligands of Chiral BINOL Derivatives for Asymmetric Addition of Alkynylzinc to Aldehydes.

CHEMINFORM, Issue 23 2008
Xiao-Wei Zou
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Synthesis of New Bifunctional BINOL Derivatives.

CHEMINFORM, Issue 16 2006
Yi-Li Zhang
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]

Enantioselective Oxidative Biaryl Coupling Reactions Catalyzed by 1,5-Diazadecalin Metal Complexes: Efficient Formation of Chiral Functionalized BINOL Derivatives.

CHEMINFORM, Issue 47 2003
Xiaolin Li
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Bifunctional Enantioselective Ligands of Chiral BINOL Derivatives for Asymmetric Addition of Alkynylzinc to Aldehydes

CHINESE JOURNAL OF CHEMISTRY, Issue 2 2008
Xiao-Wei ZOU
Abstract Four analogous binaphthyl compounds (R) -3a - 3d containing (R)-3,3,-bis(2-pyridyl) groups were synthesized by the conjugation of (R)-2,2,-dimethoxy-1,1,-binaphthyl-3,3,-diboronic acid [(R)- 2] with 2-bromopyridine, 2-bromo-5-methylpyridine, 2-chloro-4-fluoropyridine and 2-chloro-3-(trifluoromethyl)pyridine via Pd-catalyzed Suzuki reactions, respectively. The application of the four chiral ligands in combination with Et2Zn and Ti(Oi -Pr)4 to the asymmetric addition of phenylacetylene to various aldehydes has been studied. The results show that (R)- 3a and (R)- 3b are not good catalysts for the alkynylzinc addition to aldehydes, (R)- 3d shows good enantioselectivity only for the alkynylzinc addition to aliphatic aldehydes, and (R)- 3c exhibits excellent enantioselectivity for phenylethynylzinc addition to both aromatic and aliphatic aldehydes. All the four chiral ligands produced the opposite configuration of the propargylic alcohols to that of the chiral ligands. [source]

Silica Hybrid Containing (R)-2,2,-Binaphtho-20-crown-6 Moieties via the Sol-Gel Process

CHINESE JOURNAL OF CHEMISTRY, Issue 8 2003
Cheng, Yi-Xiang
(R) -6,6,-Bis (triethoxysilylethen-2-yl)-2,2,-binaphtho-20-crown6 (precursor, R -2) derived from (R)-2,2,-BINOL derivative was synthesized by Pd-catalyzed Heck reaction of (R)-6,6,-dibromo-2, 2,-binaphtho-20-crown-6 (R -1) intermediate with vinyltriethoxysilane. The hydrolysis and polycondensation of the precursor gave rise to the corresponding xerogel. Both precursor and xerogel were analysed by NMR, FT. IR, UV, CD spectra, fluorescent spectroscopy, polarimetry and elemental analysis. The precursor and xerogel can emit strong blue fluorescence and are expected to have the potential application in the separation of chiral molecules as fluorescent sensor. The precursor exhibits strong Cotton effect in its circular dichroism (CD) spectrum indicating that it is a highly rigid structure. [source]

Enantioselective Proteins: Selection, Binding Studies and Molecular Modeling of Antibodies with Affinity towards Hydrophobic BINOL Derivatives

CHEMBIOCHEM, Issue 16 2007
Brian Schou Rasmussen Dr.
Abstract In this paper, the initial steps towards the design of novel artificial metalloenzymes that exploit proteins as a second coordination sphere for traditional metal,ligand catalysis are described. Phage display was employed to select and study antibody fragments capable of recognizing hydrophobic BINOL derivatives designed to mimic BINAP, a widely used ligand in asymmetric metal-catalyzed reactions. The binding affinities of the selected antibodies towards a series of haptens were evaluated by using ELISA assays. A homology model of one of the most selective antibodies was constructed, and a computer-assisted ligand-docking study was carried out to elucidate the binding of the hapten. It was shown that, due to the hydrophobic nature of the haptens, a higher level of theoretical treatment was required to identify the correct binding modes. A small selection of the antibodies was found to discriminate between enantiomers and small structural modifications of the BINOL derivatives. The selectivities arise from hydrophobic interactions, and we propose that the identified set of antibodies provides a foundation for a novel route to artificial metalloenzymes. [source]

Enantioselective Desymmetrization of meso Epoxides with Anilines Catalyzed by a Niobium Complex of a Chiral Multidentate Binol Derivative.

CHEMINFORM, Issue 18 2007
Kenzo Arai
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]