| Abstrakt: |
Trimethylsilyl (TMS) ethers, acetates, cyclic alkane boronates (of diols) and nicotinates were evaluated as derivatives for determining the structure of n-, iso- and anteiso- long-chain alcohols and 1,2-diols. The nicotinates were the most satisfactory for both the mono- and dihydric compounds; their spectra contained a series of ions produced by radical-induced cleavage following random hydrogen abstraction from the aliphatic chain, and the differences in relative abundances of these ions reflected the position of methyl branching. In the spectra of all the derivatives studied, ions at m/z56 and 70 were characteristic of the iso- and anteiso-structures respectively, but only in the spectra of the acetates of the monohydric alcohols were the relative abundances of these ions diagnostically useful. The cyclic alkane boronates were found to be poor indicators of chain structure. Several new fragmentations of the TMS derivatives of primary alcohols are reported. |
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