Fatty acids,Part 47 The mass spectra of bis(trimethylsilyloxy) and methoxy trimethylsilyloxy ethers derived from a series of methyl epoxyoctadecenoates and methyl epoxyoctadecynoates

Twenty-two methyl epoxyoctadecenoates and four methyl epoxyoctadecynoates were converted to bis(trimethylsilyloxy) and methoxy trimethylsilyloxy derivatives for mass spectroscopic examination at 17 eV. From the results the position of the ether groups (and hence of the epoxide functions) can be determined. Additionally it is possible to discover whether the unsaturated group lies between the ether groups and the ester function or between the ether groups and the terminal methyl and to differentiate those esters of the type -CH(OR)CH(OR)(CH₂)_nCH=CH- where n = 1 from those in which n > 1. The major fragmentation pathways are outlined.