I. The Reciprocal Solvent Influence of Some Optically Active Compounds. II. The Nature of Green Ethyl Tartrate

Lamberton, Alexander Hugh (1937) I. The Reciprocal Solvent Influence of Some Optically Active Compounds. II. The Nature of Green Ethyl Tartrate. PhD thesis, University of Glasgow.

Abstract

When an optically active substance (say dA) is dissolved in or mixed with an inactive liquid it is in general found that its specific rotation has undergone alteration; nor is the volume of the mixture exactly equal to the combined volumes of the unmixed constituents. Similarly it is to be expected that when dA is mixed with an active liquid (say dB) neither the rotations nor the volumes of the components will be exactly additive. The same considerations will apply to the mixture of dA with the antimere 1B. In the case of the mixtures dA, dB and dA, 1B the following questions naturally arise: (i) What proportion of the change in rotation on mixture is to be attributed to each component? (ii) Does dA affect the rotation of dB and IB to a varying1 degree and, conversely, is dA differently affected by dB and IB? (iii) Is the volume change the same in each case? The object of my research has been firstly to obtain data for some cases where reciprocal solvent influence was considerable and secondly to find out what inferences, if any, could be drawn as to the difference or identity of the solvent influence of the d- and 1- forms of one compound upon an independent optically active compound. The latter object involved answering, if possible, the questions tabulated above.The experimental work carried out fell naturally into three parts. These were:-(i) Rotational and density measurements of mixtures of 1-nicotine and with ethyl d-tartrate, racemate and mesotartrate. (ii) Rotational and density measurements of mixtures of 1-nicotine with iso-butyl d-tartrate, 1-tartrate, racemate and mesotartrate. (iii) Accurate and delicate density measurements of mixtures of 1-menthyl acetate with d- and 1-iso-butyl tartrates.The results of the research may be cursorily summarised as follows: (i) A considerable mutual solvent effect was shown, as far as optical rotation was concerned. (ii) The proportion of the change in rotation which should be attributed to each component could only be derived on the assumption that there was no asymmetric solvent effect, e.g. that the effect of dA on dB and IB was identical, while dA was also affected identically by dB and IB. (iii) There was no evidence that such an asymmetric solvent effect (as defined above) actually existed, but on the other hand no experiment could be devised which would prove its absence. (iv) In the case of the density measurements of mixtures of 1-mentnyl acetate with d- and 1-iso-butyl tartrates only an extremely small density difference was observed. I would be very reluctant to claim that such a small difference was outside the limits of experimental error.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Organic chemistry
• Date of Award: 1937
• Depositing User: Enlighten Team
• Unique ID: glathesis:1937-80092
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 03 Mar 2020 09:18
• Last Modified: 03 Mar 2020 09:18
• URI: https://theses.gla.ac.uk/id/eprint/80092