Optically active helical poly(α,β-unsaturated ketone) from anionic polymerization of (S)-3-acrylyl-2,2′- bis(methoxymethoxy)-1,1′-binaphthyl

2014 ◽  
Vol 92 (7) ◽  
pp. 647-652
Author(s):  
Yehui Chen ◽  
Liwen Yang ◽  
Nianfa Yang ◽  
Zhusheng Yang
Keyword(s):  
Anionic Polymerization ◽  
Optical Rotation ◽  
Helical Structure ◽  
Optically Active ◽  
Unsaturated Ketone ◽  
Model Compounds ◽  
Specific Optical Rotation ◽  
G Value ◽  
Circular Dichroïsm ◽  
Structure In Solution

(S)-3-acrylyl-2,2′-bis(methoxymethoxy)-1,1′-binaphthyl (3a) was synthesized and anionically polymerized using n-BuLi as an initiator. The polymer derived from 3a had a tremendous specific optical rotation [Formula: see text] = −304.2, while that of the monomer 3a is −68.7. Poly-3a was confirmed to exist in the form of a one-handed helical structure in solution by means of comparing the specific optical rotation, the circular dichroism, and UV-vis spectra with that of 3a and the model compounds such as (S)-3-propionyl-2,2′-bis(methoxymethoxy)-1,1′-binaphthyl (3b) and (S)-3-heptanoyl-2,2′-bis(methoxymethoxy)-1,1′-binaphthyl (3c). This conclusion was also confirmed by the fact that the g value of poly-3a is about 15 times of that of the monomer 3a.

Synthesis and properties of optically active helical polymers from (S)-3-functional-3′-vinyl-BINOL derivatives

RSC Advances ◽  
2016 ◽  
Vol 6 (47) ◽  
pp. 41103-41107 ◽  
Author(s):  
Chunhui Zhao ◽  
Kunbing Ouyang ◽  
Jin Zhang ◽  
Nianfa Yang
Keyword(s):  
Circular Dichroism ◽  
Optical Rotation ◽  
Optically Active ◽  
Circular Dichroism Spectra ◽  
Specific Optical Rotation ◽  
Helical Polymers ◽  
Vinyl Polymers ◽  
Circular Dichroïsm

Helical vinyl polymers bearing N-heterocycles substituent BINOL derivatives were synthesized. The specific optical rotation and circular dichroism spectra data show the obtained polymers can keep a prevailing helicity of backbone in solution.

Optical Activity of Symmetric Compounds in Chiral Media. I. Induced Circular Dichroism of Unbound Substrates

1971 ◽  
Vol 49 (4) ◽  
pp. 624-631 ◽  
Author(s):  
L. D. Hayward ◽  
R. N. Totty
Keyword(s):  
Circular Dichroism ◽  
Carbonyl Compounds ◽  
Optical Rotation ◽  
Optically Active ◽  
Asymmetric Induction ◽  
Azo Compounds ◽  
Induced Circular Dichroism ◽  
Chiral Media ◽  
Circular Dichroïsm ◽  
Rotational Strengths

In the presence of chiral environment compounds, C, optical rotation is induced in symmetric substrates, S, and may be detected as circular dichroism in the electronic spectra of the solutions. Thus the n − π* transitions of symmetric and racemic carbonyl compounds, and of symmetric nitro and azo compounds, become optically active when these S are dissolved in chiral hydrocarbons, ketones, or carbinols, or in solutions of these C in achiral solvents. The rotational strengths of the induced circular dichroism bands of S are solvent, temperature, and concentration dependent. Only limited correlation of the sign and magnitude of the induced bands with the stereochemistry of C and S is evident on the data so far accumulated. Halogenated achiral solvents enhance the intensity, and, in some cases reverse the sign of the induced bands.A new mechanism of asymmetric induction is proposed in which specific bonding of C with S is not prerequisite.

Syntheses and circular dichroism (CD) spectra of optically active polyoxazolines and their model compounds

1992 ◽  
Vol 25 (23) ◽  
pp. 6322-6331 ◽  
Author(s):  
Yeong Soo Oh ◽  
Toshimasa Yamazaki ◽  
Murray Goodman
Keyword(s):  
Circular Dichroism ◽  
Optically Active ◽  
Cd Spectra ◽  
Model Compounds ◽  
Circular Dichroïsm

scholarly journals POLARIMETRIC RESEARCH OF PHARMACEUTICAL SUBSTANCES IN AQUEOUS SOLUTIONS WITH DIFFERENT WATER ISOTOPOLOGUES RATIO

2018 ◽  
Vol 10 (5) ◽  
pp. 243
Author(s):  
A. V. Syroeshkin ◽  
T. V. Pleteneva ◽  
E. V. Uspenskaya ◽  
O. V. Levitskaya ◽  
M. A. Tribot-laspiere ◽  
...  
Keyword(s):  
Quality Control ◽  
Ascorbic Acid ◽  
Heavy Water ◽  
Optical Rotation ◽  
Optically Active ◽  
Specific Optical Rotation ◽  
Methodology Development ◽  
Pharmaceutical Substances ◽  
Kinetic Mechanisms ◽  
Water Isotopologues

Objective: Methodology development for quality control of optically active pharmaceutical substances based on water isotopologues.Methods: Solutions of L-ascorbic acid, glucose, galactose and valine stereoisomers were prepared using deuterium depleted water (DDW-«light» water, D/H=4 ppm), natural deionized high-ohmic water (BD, D/H=140 ppm), heavy water (99.9% D2O). The optical rotation was observed using an automatic polarimeter Atago POL-1/2. The size distribution of giant heterogeneous clusters (GHC) of water was recorded by low angle laser light scattering (LALLS) method.Results: The infringement of Biot’s Law was found for solutions of ascorbic acid, expressed in the absence of a constant value of the specific optical rotation  at a concentration of below 0.1%, depends on the D/H ratio. The inequality was established in absolute values of optical rotation for L-and D-isomers of valine in solutions with different ratios of hydrogen isotopologues. The mutarotation of glucose confirmed the first-order kinetics, and the activation energies were statistically distinguishable for BD and DDW. The mutarotation of the natural galactose D-isomer proceeded with a lower energy consumption compared to the L-isomer. In heavy water, the mutarotation of monosaccharides had different kinetic mechanisms. Polarimetric results correlated with the number and size of GHC, which confirmed the possibility of chiral solvent structures induction by optically active pharmaceutical substances.Conclusion: In the optically active pharmaceutical substances quality control there should be considered the contribution of induced chiral GHC of water to the optical rotation value that depends on the isotopic D/H ratio, the substance nature and the form of its existence at a given pH.

Radical Polymerization of a Novel Methacrylamide Derivative

2015 ◽  
Vol 1095 ◽  
pp. 359-362
Author(s):  
Chao Yuan ◽  
Ping Liu ◽  
Long Hua Chen ◽  
Yuan Zhang
Keyword(s):  
Radical Polymerization ◽  
Optical Rotation ◽  
Optically Active ◽  
Optically Active Polymers ◽  
Specific Optical Rotation ◽  
Polymer Yield ◽  
Molecular Weights ◽  
H Nmr

The radical polymerization of a novel methacrylamide derivative, N-[o-(4-ethyl-4, 5-dihydro-1, 3-oxazol-2-yl) phenyl] methacrylamide ((S)-EtOPMAM), was carried out to obtained optically active polymers. The polymer yield and the chiroptical behavior of the resultant polymers have been examined in detail by using IR and 1H NMR spectroscopies in comparison with our previous observation. The polymers showed relatively high molecular weights (Mn=8000-16000) and largest specific rotations ([α]25D =+120.6o). Particularly, the largest specific optical rotation of the polymer is almost the six times of the monomer.

New Approach to the Theory of Circular Dichroism

1998 ◽  
Vol 63 (8) ◽  
pp. 1187-1201 ◽  
Author(s):  
Jaroslav Zamastil ◽  
Lubomír Skála ◽  
Petr Pančoška ◽  
Oldřich Bílek
Keyword(s):  
Electromagnetic Wave ◽  
Circular Dichroism ◽  
Electromagnetic Waves ◽  
Maxwell Equations ◽  
Optically Active ◽  
Semiclassical Approach ◽  
New Approach ◽  
Isotropic Media ◽  
New Formula ◽  
Circular Dichroïsm

Using the semiclassical approach for the description of the propagation of the electromagnetic waves in optically active isotropic media we derive a new formula for the circular dichroism parameter. The theory is based on the idea of the time damped electromagnetic wave interacting with the molecules of the sample. In this theory, the Lambert-Beer law need not be taken as an empirical law, however, it follows naturally from the requirement that the electromagnetic wave obeys the Maxwell equations.

First optically active ferricinium salts: A circular dichroism study

1992 ◽  
Vol 438 (3) ◽  
pp. C26-C28 ◽  
Author(s):  
Viatcheslav I. Sokolov ◽  
Irina A. Mamedyarova ◽  
Marina N. Nefedova ◽  
Günther Snatzke
Keyword(s):  
Circular Dichroism ◽  
Optically Active ◽  
Circular Dichroïsm
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