Optical rotatory power

Normal measurements of optical activity are concerned with the ability of the optically active substance to rotate the plane of polarization of plane polarized light, its specific optical rotatory power ( ) being given by... 

O.D., abbrev. (optisches Drehungavermogen) optical rotatory power, od. dgL, abbrev. (oder dergleichen) or the like, bde, a. waste, deserted. 

See Partington, A History of Chemistry, IV 856. Lowry published Optical Rotatory Power (London Longmans, 1935). See also Lowry, "La dispersion rotatoire optique Hommage a la memoire de Biot (17141862)," Conference faite le 9 decembre 1925 devant la Societe de Chimie Physique, JCP 23 (1926) 565585. 

T. M. Lowry, Optical Rotatory Power, Longmans Green, London, 1935 republished by Dover,... 

Kauzmann, W., Clough, F. B., and Tobias, I. (1961) The principle of pairwise interactions as a basis for an empirical theory of optical rotatory power. Tetrahedron 13, 57-105. 

The thioaldonic phenylhydrazides obtained by reduction of saccharide formazans condense with benzaldehyde to give 1,3,4-thiadi-azolines, characterized by their high optical rotatory power.234,235... 

It is the off-diagonal elements of (13.7) that give rise to cross polarization (S, = = S22) as well as the nonzero elements S13, S14, S23, and S24 in (13.8). That S3 and S4 should be nonzero for optically active particles follows from elementary physical reasoning optical rotatory power in a homogeneous medium causes the direction of vibration to be rotated upon transmission of linearly polarized light by the medium. However, optical activity of the bulk... 

The optical rotatory power was found to be very high. Considering the D-ray of sodium (589 nm), the optical rotatory power was + or -7000° moE1 L dm-1. 

Fig. 14. The relationship between optical rotatory power and tail-to-tail content of polypropylene oxides [Oguni et al. (62)]...

Methyl 2,4-dimethylhexanoate (diastereoisomeric mixture) was 16.6% of the original mixture. Methyl 4-methylheptanoate 3.2% of the original mixture was recovered in such a small quantity that its optical rotatory power could not be determined. 

Estimation of Catalytic Activity. The catalytic activities of the copolymers on the hydrolysis of polysaccharides were estimated, with the measurement of increase in reducing sugar in the reaction mixture with reaction time according to Somogyi method (22). The hydrolysis rates of sucrose were determined from the measurement of optical rotatory power... 

Some of these topics have been elaborated in Section 1.2, where the reader is referred to the many excellent monographs and articles which are available, and which fully explore the current aspects of the stereochemistry of molecules and the importance of stereochemical considerations of appropriate reaction processes. This section is devoted to the experimental determination of optical rotatory power. 

Essentially, the origin of spontaneous chiral resolution is the same as the previous example. When molecules with the same chiral conformation form small chiral domains due to packing entropy effects, the same chiral conformation of molecules is stabilized when they approach the chiral domain. Thus both chiral domains with different chiral conformations grow, resulting in spontaneous chiral resolution [6-8]. Chirality enhancement occurs even in such chiral domains. For instance, chirality in both segregated chiral domains is enhanced by doping nonchiral bent-shaped molecules (BSMs) with nonchiral rod-shaped molecules (RSMs), as observed by circular dichroism (CD) or optical rotatory power (ORP) [9],... 

In general, small specific rotations should be expected for such adamantane derivatives since a large reduction in optical rotatory power should occur when pairwise interactions are greatly reduced by distance. The resolution of several tetrasubstituted adamantanes (62-65) has been attempted 178 179> 247f Mes-ured rotations, as expected 4> are quite low. Only 65, the formal analogue of lactic acid, has been proven to be optically active 178>179f by a confirmatory approach. 

Quantitative conclusions regarding the reduction of optical rotatory power of these derivatives by the increased distance of the pairwise interactions must, of course, await optical purity determinations. Qualitatively, however, expectations are obviously confirmed 179 ... 

C. S. Hudson, A relation between the chemical constitution and the optical rotatory power of the phenylhydrazides of certain acids of the sugars, J. Am. Chem. Soc., 39 (1917) 462-470. 

Taking into account the regularity with which stachyose falls in the sequence consisting of sucrose, raffinose, stachyose, etc. (see Sections III and IV on optical rotatory power and chromatographic relations), together with the concordant chemical and biochemical studies on... 

Abstract This review summarizes the literature survey on chiral recognition from a theoretical view point. Nevertheless, experimental results in the gas phase are reported when they are relevant for the theoretical calculations. The review is divided into the following sections general considerations experiment vs. theory pure theoretical results solvent effects metals as glue optical rotatory power and conclusions. 

The chiral discrimination in the self-association of chiral l,3a,4,6a-tetrahydroi-midazo[4,5-d]imidazoles 3 has been studied using density functional theory methods [37], (Scheme 3.20). Clusters from dimers to heptamers have been considered. The heterochiral dimers (RR SS or SS RR) are more stable than the homochiral ones (RR RR or SS SS) with energy differences up to 17.5 kJ mol-1. Besides, in larger clusters, the presence of two adjacent homochiral molecules imposes an energetic penalty when compared to alternated chiral systems (RR SS RR SS...). The differences in interaction energy within the dimers of the different derivatives have been analyzed based on the atomic energy partition carried out within the AIM framework. The mechanism of proton transfer in the homo- and heterochiral dimers shows large transition-state barriers, except in those cases where a third additional molecule is involved in the transfer. The optical rotatory power of several clusters of the parent compound has been calculated and rationalized based on the number of homochiral interactions and the number of monomers of each enantiomer within the complexes. 

The measurement of the optical rotatory power of chiral substances has been of major importance in the characterization of the enantiomeric purity. A number of computational techniques have been developed in the last year to evaluate this property. A recent review [142] shows in detail the advances in this field. Application of the new implementation of the evaluation of the optical rotatory power has allowed to the study of the conformational [143-146] and solvent effects [147,148] on the magnitude and sign of the optical rotation power. 

Ferraro and coll, used canonical transformation of the Hamiltonian to resolve the average optical rotatory power of a molecule into atomic contributions, based on the acceleration gauge for the electric dipole, and/or the torque formalism [151], This method has been applied to the study of the conformational profile of the optical rotatory poser of hydrogen peroxide and hydrazine [152]. 

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