Fatty acids, Part X. Raman spectra of all dimethylene interrupted methyl cis, cis-octadecadienoates and octadecadiynoates.

The Raman spectra of all the dimethylene interrupted methyl cis, cis-octadecadienoates and octadecadiyonates have been studied. The Raman band positions and their relative intensities for the v(C=C),v(C=C),v(C-H) and beta (CH2) modes are recorded. The height intensity of the bands arising from v(C=C) relative to v(C=O) provides a means of determining the number of cis-ethylenic bonds in a mono-ester. In the acetylenic series, the intensity of the bands arising from v(C=C) relative to v(C=O) failed to indicate with certainty the number of acetylenic bonds in the mono-esters studied, due to the weak intensity of the band due to v(C=O). However a better correlation between the relative intensities of the v(C=C) and beta (CH2) bands is established instead. An attempt to correlate the areas under the bands due to v(C=C), (C=C), (C=O) and beta (CH2) failed to produce any significant results. The Raman spectra of the methyl octadec-cis-10-en-5-ynoate and methyl octadeca-5, 10-diynoate are also recorded.