Question

v) The resonances at 6.63 and 7.17 have a J of 2 Hz.

a. What does J stand for?

b. What information can you derive from a value of 2?

vi) Based on your spectra above your answer to iv) and v), is the chemical in the bottle compound A, B or C?

Need help with all of question 3. Thank you :)

QUESTION 3 A chemical bottle has been found in the lab, unfortunately it is incorrectly labelled and only has the molecular formula listed (C H1o04). It has been deduced that it is one of three constitutional isomers, compounds A B or C below. The H NMR spectrum is as follows: a 3.85 (6H, s) 6.63 (1H, , J2Hz).7.17 (2H, d, J 2Hz) (note that the carboxylic acid proton is not observed). Work though each of the questions below before writing your answer .o согн i) How many signals would be observed in the H NMR spectrum of A? Note that the carboxylic acid proton will not be observed 0% mark] ) How many signals would be observed in the H NMR spectrum of B? Note that the carboxylic acid proton will not be observed 1% mark] ii) How many signals would be observed in the 'H NMR spectrum of C? Note that the carboxylic acid proton will not be observed 1% mark v) For each of the compounds above predict their 'H NMR spectrum. (Note marks will be awarded for chemical shift, multiplicity and integration of each peak). The carboxylic acid proton will not be observed A. II mark B. II mark] QUESTION 3 coNINUED C. [I mark]

Answer 1

J is called coupling constant. It is the distance between the peak in a given multiple mu a measure of the magnitude of splitting effect ii) well J value is less means 0-2 or 2-3 if protons are metal is Para with respect to each other likes if distance b/t protons is more than J value is less \r\n these are total 3 signals ii) there are total 5 signals iii) there are total 3 signals