Question

answer all questions.

Consider the following compound for question 3 & 4. Hon this carbon 3. Answer the following questions about H NMR spectroscopy. a. How many signals would you expect to appear in the 'H NMR spectrum of this compound? b. What would the multiplicity (splitting) of the peak corresponding to H? 4. Answer the following questions about "C NMR spectroscopy. a. How many signals would you expect to appear in the "C NMR spectrum of this compound? b. What would be the multiplicity (splitting) of the peak corresponding to the carbon labeled "G"? 5. Below is a 'H NMR spectrum. Circle the structure that best corresponds to the spectrum. Briefly justify your choice by explaining how the information in the spectrum supports the structure you have chosen. nog rich lion rich ppm

Answer 1

1. All protons of each carbon different (non-equivalent) and 3 positions of the benzene ring does not contain proton therefore does not give signals.

2. In 1H-nmr 10 signals would be appeared.

3. -*CH2CH3, 4 mulitiplicity (quartet) are seen.

4. For 13 C- nmr 12 signals would be appeared.

5. And in off- resonance 13C-nmr doublet are seen for -CH- in benzene ring.

6. First structure will be correct.

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