2- Pentyne mass spectrum

Pentane, 1 -pentene, and 1 -pentyne are low-Poiling hydrocarbons that have different molecular ions in their mass spectra. Match each hydrocarbon to its mass spectrum. 

As can be seen from the mass spectrum of 1-pentyne (Fig. 8.15), fragmentation of the type... 

Both the molecular ion, mIz 68, and the propargyl cation, mIz 39, are seen in the mass spectrum of 1-pentyne (Figure 14.9). Also seen is the ethyl cation, miz 29. 

The mass spectra of alkynes are very similar to those of alkenes. The molecular ion peaks tend to be rather intense, and fragmentation patterns parallel those of the alkenes. As can be seen from the mass spectrum of 1-pentyne (Fig. 4.18), an important fragmentation is the loss of an ethyl radical via an a-cleavage to produce the propaigyl ion (m/z = 39). Similarly, loss of methyl radical in an a-cleavage... 

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