Fragmentation Patterns of Ethers and Sulfides

The fragmentation patterns of the thiols are very similar to those of the alcohols. As alcohols tend to undergo dehydration under some conditions, thiols tend to lose the elements of hydrogen sulfide, giving rise to an M - 34 peak. 

Aliphatic ethers tend to exhibit molecular ion peaks that are stronger than those of alcohols with the same molecular weights. Nevertheless, the molecular ion peaks of ethers are stiU rather weak. Principal modes of fragmentation include a-cleavage, formation of carbocation fragments through 

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The mass spectrum of di- ec-butyl ether (Fig. 4.37) shows the same fragmentations. There are two possible a-cleavages in this compound, however. Loss of a methyl radical gives the very small 

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