107 



The species at m/z 71 will undergo a subsequent loss of H, via elimination 



resulting in the formation of a triple bond at the methyl terminal to produce the ion 

 at m/z 69; this is identical to the fragment occurring from loss of HjO from the m/z 

 87 species. In addition, m/z 71 undergoes additional losses of CO and H2CO, 

 whereas the m/z 69 ion can only further lose CO. The direct neutral losses of CO 

 from m/z 89 and m/z 87 are similar. However, again, the m/z 61 ion formed from 

 m/z 89 can undergo losses of H2, and HjO, whereas the ion at m/z 59 cannot. It is 

 interesting to note that the m/z 59 ion will undergo homolytic cleavage to form an 

 odd-electron ion at m/z 42, via the loss of a HO' radical. This is relatively 

 uncommon and unfavorable for an even-electron precursor [79]. Since the charge 

 is retained on the odd-electron species, this fragment arises from cleavage of a single 

 bond, i.e. between the hydroxyl group and the carboxyl carbon. A fragmentation 

 involving cleavage of two bonds would necessitate charge migration for production 

 of an odd-electron fragment. 



The only cases where a direct loss of formaldehyde occurs are from m/z 89 

 directly, or from m/z 71, which resulted via the loss of H2O from the m/z 89 species. 

 In contrast to this, the loss of CO2 occurs from all three major species (m/z 89, m/z 

 87, and m/z 85). In each case the products formed depict losses of hydrogens 

 characteristic of the precursor species. If an additional two hydrogens are lost via 

 loss of formic acid, then the required number of hydrogens to constitute these losses 

 are only present when losses come from the m/z 89 and m/z 87 species. 



