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Aromatic structures, and mass spec, molecular ion, relative

1.(refering to dexchlorpheniramine, pilocarpine, and 9-aminoacridine)--GO TO WWW.CHEMFINDER.COM TO LOOK UP STRUCTURES FOR THESE COMPOUNDS)--
For each ring in each structure, indicate if it is aromatic. Rationalize your decision for each ring (even those that are not aromatic). Make sure to indicate which (if any) lone pair electrons are part of the pie system.

2. .(refering to dexchlorpheniramine, pilocarpine, and 9-aminoacridine)Indicate the m/z value at which the molecular ion of each structure would appear.

3. Assuming the structures above gave molecular ion abundances of 12, 70, and 23(dexchlorpheniramine, 9-aminoacridine and pilocarpine, respectively), what abundances would you expect for the M+1 and the M+2 peaks for each structure?

4.One mechanism of fragmentation is loss of a neutral radical by cleavage of a bond from which one electron lost. What is the m/z ratio of the most stable cationic fragment that can be generated from dexchlorpheniramine by this mechanism?show the structure of the fragment and discuss charge stabilization.

5.The base peak in the dexchlorpheniramine mass spectrum occurs at m/z 203. A peak with relative intensity 33.1 occurs at m/z 205. interpret this information with reference to the original mass and molecular formula of the parent molecule.

6.The base peak in the dexchlorpheniramine mass spectrum (described in question 5) corresponds to a fragment generated through an intramolecular elimination reaction. Identify the atom that acts as a base in this elimination and draw both products. Indicate which product appears at m/z 203 as a cation radical.

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Solution Summary

Explanation given to six problems related to Mass spectroscopy