32750-01-9Relevant academic research and scientific papers
Direct enantioseparation of axially chiral 1,1′-biaryl-2,2′-diols using amidine-based resolving agents
Hirose, Takuji,Kodama, Koichi,Takase, Fusato
, p. 18162 - 18170 (2021/06/07)
Amidine-based optically active resolving agents for enantiomer separation of axially chiral 1,1′-biaryl-2,2′-diols have been developed. A strongly basic amidine bearing no substituents on its nitrogen atoms enables the formation of their diastereomeric salts upon being mixed with weakly acidic phenol derivatives. Enantiopure 1,1′-biaryl-2,2′-diols can be obtained in high yields after only one crystallization of their salts with the chiral amidine derived from dehydroabietic acid. X-ray crystallography revealed that the amidine moiety forms a salt with the phenol group and additional intermolecular NH/π interactions contribute to the efficient chiral recognition process.
Hexafluoroisopropanol-Enabled Copper-Catalyzed Asymmetric Halogenation of Cyclic Diaryliodoniums for the Synthesis of Axially Chiral 2,2′-Dihalobiaryls
Ke, Jie,Zu, Bing,Guo, Yonghong,Li, Yingzi,He, Chuan
, p. 329 - 333 (2021/01/13)
An efficient asymmetric halogenation of cyclic diaryliodonium salts is demonstrated, which gives access to a wide range of axially chiral 2,2′-dihalobiaryls in good to excellent yields and with excellent enantioselectivities. The use of CuX with chiral bisoxazoline ligand and tetrabutylammonium halides in the unique solvent of hexafluoroisopropanol (HFIP) led to the best results in the process. The axially chiral 2,2′-dihalobiaryls can be transformed into a number of enantiopure chiral ligands that could be potentially useful in asymmetric catalysis.
Enantioselective Synthesis of Axially Chiral Biaryls via Cu-Catalyzed Acyloxylation of Cyclic Diaryliodonium Salts
Zhu, Kai,Xu, Kai,Fang, Qi,Wang, Yi,Tang, Bencan,Zhang, Fengzhi
, p. 4951 - 4957 (2019/05/24)
We report here a Cu-catalyzed enantioselective acyloxylation of cyclic diaryliodonium salts. With readily available cyclic diaryliodonium salts and ubiquitous aliphatic or (hetero)aromatic carboxylic acids as the starting materials, various axially chiral
Macromolecular helicity induction and memory in a poly(biphenylylacetylene) bearing an ester group and its application to a chiral stationary phase for high-performance liquid chromatography
Ishidate, Ryoma,Shimomura, Kouhei,Ikai, Tomoyuki,Kanoh, Shigeyoshi,Maeda, Katsuhiro
, p. 946 - 948 (2015/08/24)
An optically inactive poly(biphenylylacetylene) bearing an ester group at the 4′-position of the pendants formed a preferred-handed helical conformation and biased axial chirality in the pendants through a noncovalent interaction with a chiral alcohol, both of which were retained (memorized) even after removal of the chiral alcohol. The chiral stationary phase for high-performance liquid chromatography, prepared by coating the polymer with macromolecular helicity memory on silica gel, showed good chiral recognition ability towards various racemates.
Catalyst components for the polymerization of olefins
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, (2014/12/09)
A solid catalyst component for the polymerization of olefins comprising Mg, Ti, Cl and at least an electron donor compound which is the reaction product obtained by bringing into contact a Mg compound and a Ti compound having at least a Ti-halogen bond with an electron donor selected from specific diphenol derivatives.
Chiral phosphoric acid catalyzed enantioselective synthesis of β-amino-α,α-difluoro carbonyl compounds
Kashikura, Wataru,Mori, Keiji,Akiyama, Takahiko
supporting information; experimental part, p. 1860 - 1863 (2011/06/20)
A biphenol-based chiral phosphoric acid bearing a 9-anthryl group at each of the 3,3′-positions catalyzed the asymmetric Mannich-type reaction of N-Boc imine with difluoroenol silyl ethers in the presence of MS3A in THF to afford β-amino-α,α-difluoroketon
Separating agent for enantiomeric isomers
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Page/Page column 7; 8; 9, (2010/04/23)
The present invention provides a separating agent for enantiomeric isomers exhibiting high separation power. That is, the present invention provides a separating agent for enantiomeric isomers including, as an active ingredient, a polysaccharide derivative having at least part of hydrogen atoms of hydroxyl groups of a polysaccharide such as cellulose or amylose substituted by at least one of atomic groups represented by the following general formulae (I) and (II): (in the formulae, R represents a substituted or unsubstituted aromatic group, or a linear, branched, or cyclic aliphatic group).
OPTICALLY ACTIVE 2,2'-BIPHENOL DERIVATIVE AND METHOD FOR PRODUCING THE SAME
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Page/Page column 15, (2010/11/03)
An optically active 2,2'-biphenol derivative and a production method that enables simple and efficient production of this compound. More specifically, an optically active biphenol derivative represented by the following formulas (1) and (2), a method for optically resolving a biphenol derivative represented by formula (2'), a production method of an optically active biphenol derivative (1) comprising a step for reacting a Br?nsted acid with a biphenol derivative (2), and a production method of an optically active biphenol derivative (3) comprising a step for reacting a Lewis acid with an optically active biphenol derivative (1) or an optically active biphenol derivative (2). In the following formulas, R1 represents, for example, a primary or secondary alkyl group having 1 to 10 carbon atoms, * represents an axially asymmetric center, X represents a halogen atom, and R2 represents a tertiary alkyl group having 4 to 6 carbon atoms.
Filler for Optical Isomer Separation
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Page/Page column 9; 11, (2009/05/28)
A polymer compound derivative, obtained by modifying part of the hydroxy or amino groups of a polymer compound having the hydroxy or amino groups with molecules of a compound represented by the following general formula (I): A-X—Si(Y)nR3-n (I), where A represents a reactive group which reacts with a hydroxy or amino group, X represents an alkylene group which has 1 to 18 carbon atoms and which may have a branch, or an arylene group which may have a substituent, Y represents a reactive group which reacts with a silanol group to form a siloxane bond, R represents an alkyl group which has 1 to 18 carbon atoms and which may have a branch, or an aryl group which may have a substituent, and n represents an integer of 1 to 3.
New 2,2′-substituted 6,6′-dimethylbiphenyl derivatives inducing strong helical twisting power in liquid crystals
Holzwarth, Richard,Bartsch, Richard,Cherkaoui, Zoubair,Solladie, Guy
, p. 3536 - 3541 (2007/10/03)
New optically active tetra-ortho-substituted biphenyl chiral dopants for nematic liquid crystals are described. It was shown, with respect to our previous results, that biphenyl chiral dopants bearing only mesogenic residues on their 2,2′-positions and wi
