17 (5 pts.) The best way to actually characterize your product is to use proton

Question

17 (5 pts.) The best way to actually characterize your product is to use proton NMR, using NMR you could distinguish exactly which ester you had made. Shown below are proton NMR spectra for several esters. For YOUR ESTER (ONLY), assign each signal in the proton NMR to hydrogens in the provided structures, i.e. assign the set of protons labeled "a" to one of the peaks, the set of protons labeled "b" to one of the peaks etc. BE CAREFUL, some peaks may be assigned to more than one set of protons, either because of magnetic equivalence or because of accidental overlap of the peaks! 3H singlet 4H multiplet 2H 3H let 11 1087 3H singlet 2H 4H multiplet multiplet 2H triplet 3H et 11 10 0 3H CH2 CHd e CHsinglet 2H triplet mult 1H multiplet 0 b CHz 3H 2H 6H multiplet multiplet 2H triplet triplet 109 6543

Explanation / Answer

In the first proton NMR spectra, the peak due to proton labelled as "a" is assigned to that peak which has been marked as 3H singlet as the proton labelled as "a" consists 3H and also there is no nearby proton so it results to singlet. The proton labelled as "b" is assigned to that peak which has been marked as 2H triplet, as this proton consists of 2H and also there are two (=n) nearby protons to it so it results in (n+1) i.e. 2+1=3 or triplet. The peak marked as 4H multiplet is due to the overlappping of ttwo protons labelled as "c" and "d"

Similarly in the second proton NMR spectra, the peak due to proton labelled as "a" is assigned to that peak which has been marked as 3H singlet as the proton labelled as "a" consists 3H and also there is no nearby proton so it results to singlet. The proton labelled as "b" is assigned to that peak which has been marked as 2H triplet, as this proton consists of 2H and also there are two (=n) nearby protons to it so it results in (n+1) i.e. 2+1=3 or triplet. The peak marked as 4H multiplet is due to the overlappping of two protons labelled as "c" and "d". The peak marked as 2H multiplet is due to the overlappping of protons labelled as "e" as it consists of 2H and there are 3+2 =5 nearby protons. so it results in multiplet as there is overlapping due to multiplicity arise from 5 H which results in sextet. The peak marked as 3H triplet is due to proton labelled as "f" as it consists of 3H and 2 nearby protons.

In the third proton NMR spectra, the peak due to proton labelled as "a" is assigned to that peak which has been marked as 3H singlet as the proton labelled as "a" consists 3H and also there is no nearby proton so it results to singlet. The proton labelled as "b" is assigned to that peak which has been marked as 2H triplet, as this proton consists of 2H and also there are two (=n) nearby protons to it so it results in (n+1) i.e. 2+1=3 or triplet. The peak marked as 2H multiplet is due to the proton labelled as "c". Sonce this proton has several nearby protons so it results in multiplet. The peak marked as 1H multiplet is due to the protons labelled as "d" as it also consists of several nearby protons, so it results in multiplet The peak marked as 6H doublet is due to proton labelled as "e" as it consists of of 6 H and 1 nearby proton.

In the fourth proton NMR spectra, the peak due to proton labelled as "a" is assigned to that peak which has been marked as 3H singlet as the proton labelled as "a" consists 3H and also there is no nearby proton so it results to singlet. The proton labelled as "b" is assigned to that peak which has been marked as 2H triplet, as this proton consists of 2H and also there are two (=n) nearby protons to it so it results in (n+1) i.e. 2+1=3 or triplet. The peak marked as 2H triplet is due to the proton labelled as "c". Sonce it has 2 H and 2+2=4 nearby protons due to that labellled as "b" and "d".  The peak marked as 6 H multiplet is due to the proton labelled as "d", "e" and "f". The peak marked as 3H triplet is due to proton labelled as "f" as there are 3H and 2 nearby protons to that of "f" results in triplet.  

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.