a) How can you calculate the number of rings plus double bonds (r+d) based on a molecular formula?
b) Apply the r+d algorithm to the compounds below.
C3H8 C6H12O2 C6H11NO C32H25N3O2S C8H20N2 C7H9N C3H6BrN C9H11ClN4O2 C17H32Cl2 ………. ………. ………. ………. ………. ………. ………. ………. ……….Molecular composition
r+d = …
c) Collect criteria for the recognition of molecular ions from EI mass spectra.
d) Some neutral losses occurring from molecular ions are very frequent and can be reliably assigned to certain structural features. Try to assign the following neutral losses:
1 15 17 18 28 29 31 35 45 ………. ………. ………. ………. ………. ………. ………. ………. ……….Neutral loss [u]
Reasonable formula …
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