Question

Propose a fragmentation to account for each numbered peak in the mass spectrum of n-butyl isopropyl ether.

Short answer

Mass spectrometry is the technique which is used to isolate the sample on basis of its m/z ratio. This type of technique can also be used in the isolation of isotopes. Sample used can be liquid, solid or gas. Ionization methods are different for different phases. Signal will appear in the form of m/z ratio. Mass spectrometry do not detect neutral particle, it only detects charged particle. After ionization, fragmentation occurs.

Step-by-step solution

 Step-1. Mass spectrum:

Mass spectrometry is the technique which is used to isolate the sample on basis of its m/z ratio. This type of technique can also be used in the isolation of isotopes. Sample used can be liquid, solid or gas. Ionization methods are different for different phases. Signal will appear in the form of m/z ratio. Mass spectrometry do not detect neutral particle, it only detects charged particle. After ionization, fragmentation occurs.

Step-2. Mass spectrum of n-butyl isopropyl ether:

n-butyl isopropyl ether which is the molecular ion undergoes ionization followed by fragmentation and produces butyl carbocation whose m/z is 57 and propyl carbocation whose m/z value is 43. These fragments are formed via alpha-cleavage and gives peak or signal in mass spectrum.The other two fragments are formed by beta-cleavage and results in formation of carbocation species which are stable due to mesomeric effect of adjacent oxygen. These fragments have m/z value equal to 73 and 101 and give signal in mass spectrum.