XXVII.—The effect of contiguous unsaturated groups on optical rotatory power. Part VI. The influence of the carbonyl group on optical rotatory power. Part VII. The relative influences of aromatic and hydroaromatic nuclei on optical rotatory power. Part VIII. The influence on optical activity of two contiguous unsaturated groups in comparison with that of one unsaturated group at varying distances from the optically active complex

During a period of over 20 years, investigations have been carried out by one of us with a view to determining the form of the curve of rotatory dispersion, e.g., in the cases of quartz* and of a large number of typical organic compounds. These measurements were always made within the range of wave-lengths for which the medium under examination was completely transparent, since only under these conditions could the precision of the measurements be raised to a maximum by increasing the concentration of the optically-active compound and the length of the column traversed in the polarimeter. The general result has been to prove that the equation a = 2 f 2 , by which DRUDE in 1899 proposed to represent the optical rotatory power of transparent media, can be used to express the rotatory dispersion of compounds of every available type, up to the limits set by the experimental errors and by the range of transparency of the medium.

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Optical rotatory power. I—A theoretical calculation for a molecule containing only isotropic refractive centres

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1934.0075 ◽

1934 ◽

Vol 144 (853) ◽

pp. 655-675 ◽

Cited By ~ 41

Keyword(s):

Theoretical Calculation ◽

Optical Activity ◽

Chemical Structure ◽

Central Atom ◽

Optical Rotation ◽

Rotatory Power ◽

Theoretical Formula ◽

Optical Rotatory ◽

Present Communication ◽

Optical Rotatory Power

Ever since the time of van’t Hoff and Le Bel the number investigations dependent on optical activity, or attempting to elucidate optical activity, has been very great, and it is remarkable that, even at the present time, there is no theoretical formula which gives the relation between the magnitude of the rotation and the chemical structure of the molecule concerned. The present communication supplies this want with regard to the molecule of the simplest asymmetric type: the molecule with four different groups attached to one central atom. Various special hypothese have been postulated to explain optical activity, but a few investigators have shown quite definitely that there is no necessity for any of these hypotheses. Born* and Oseen have shown independently that, if the molecule has a dissymmetric structure, the ordinary refractive properties of the atoms will account for an optical rotation. Gray* and de Mallemann have attempted calculations of formulæ for optical retatory power on this basis. However, it has not been possible to condense the numerous algebraic terms which occur in these calculaations into a compact form.

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