2-Methyl-2-pentene, mass spectrum

Example For the case of 4-methyl-1-pentene, the breakdown graph, the internal energy distribution from the photoelectron spectrum, and the 70 eV El mass spectrum are compared (Fig. 2.22). [99] From the fragmentation threshold to about... 

Fig. 2.22. Relationship of breakdown graph (a), internal energy distribution from PES (b), and mass spectrum of 4-methyl-1-pentene (c). Reproduced from Ref. [99] by permission. John Wiley Sons, 1982.

Figure 6.1.28. Mass spectrum tentatively assigned to 2,4-bis(2-methylpropyl)-8-methyl-1-nonene, the trimer of 4-methyl-1-pentene (MW = 252).

The molecular ion in the mass spectrum of 2-methyl-l-pentene appears at m z 84. Propose structural formulas for the prominent peaks at m z 69,55,41, and 29. 

Problem 12,2 Two mass spectra are shown in Figure 12.7. One spectrum is that of 2-methyl-I 2-pentene the other is of 2-hexene. Which is which Explain. 

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