Question

Problem #1. We have learned to recognize the multiplicity patterns: singlet (1 line), doublet (2 lines), triplet (3 lines), quartet (4), pentet (5) (or quintet), hextet (6), etc. When looking at actual 'H NMR spectra, it is important to realize that the outer lines of multiplets of peaks with N > 5 are often not visible. In other words, these lines are so short relative to the other lines in the multiplet that they are obscured by the baseline! a) Draw a quartet, pentet, hextet, and heptet in the boxes provided. Pay attention to the relative peak heights within each multiplet (quartet is 1:3:3:1, etc). quartet pentet hextet heptet b) How could you tell apart a quartet and a hextet, even if the outermost 2 lines of the hextet were so small that you couldn't see them? c) What would you look for to determine if a multiplet is a hextet or a heptet if the outer lines are unclear? In other words, if two reasonable people looked at the peak, counted the # of lines, and disagreed, how would you resolve the disagreement?

I have done part a) so you don't have to draw them. Please answer b and C. Thanks

Answer 1

① = you have done B, To distinguish belüeen a quartet and a Werteat, eres if the outermost 2 unes of hextet were so small, then - 0 Peak height ratio's will be different eis - both the peaks. ie relative peak anda. ® Intergral lines will also be different for .. quartett and hextedt. for egi- Lullu nextedt quarted I - Integeal line 1 0 nue AD It tells about the no. of coupling prolons. To determine if a multiplet is a hextet if the outer lines are unclear – thew High Resolution NMR- spettoscopy should be used. ot provide detailed information of chemical shifts, Jo coupling constant, multiplet patterns and relature peak areas. Zs Peace rack