Question

Steps in Spectral Identification

For your report, the following items must be completed: the point-breakdown for each item is also indicated.

¨ Use molecular formula to determine degrees of unsaturation: 2 points

IHD = # of (rings + p bonds)

¨ Identify major peaks in IR spectrum, if any: 4 points

Use the IR data tables in your lab manual and organic textbook to

determine if there are characteristic signals corresponding to the

various functional groups.

e.g.,

O—H OH single bond stretch

N—H or N—H₂ NH single bond stretch

CºC—H terminal alkyne, CH stretch

CºC, CºN triple bond stretch

H—C=O aldehyde CH stretch

C=O CO double bond stretch

C—O CO single bond stretch

Other…?

q Speculate on possible functional groups that might be present.

- Deduce structural fragments for each of the ¹H NMR spectral signals.

Usually working upfield (from high to low chemical shift) is

most efficient.

o Explain your reasoning

- Assemble the fragments to construct the molecule.

¨ Give the structure of the compound. 2 points

¨ Assign the signals in the ¹H NMR spectra to specific protons. 6 points

¨ Assign carbons to the peaks in the ¹³C NMR spectrum 6 points

Unknown 014 MF C4H80 Mw 72 %C 66.6 %H 11.2 8 Mass Spec. D relativ m/z abund. 3124 2 2 se- Freknwh 40- 72 36 1000 25aa 3see