nmr

Shift	Multiplicity	Number of Hydrogens	Assignment	Reasoning
7.19	d	2H	P	These hydrogens will have shifts of around 7 ppm because they are located on an aromatic ring. They are the most deshielded on the ring because of the inductive effects of the nearby oxygen. They both appear as doublets because they each have only one hydrogen neighbor close enough to couple with.
6.86	d	2H	O	These hydrogens are located on an aromatic ring, so their shifts are around 7 ppm. It is unclear why they are reported as doublets, since they each have two hydrogen neighbors that they could easily couple with, leading us to predict that they would appear as triplets.
6.61	d	1H	N	This hydrogen is located on an aromatic ring, opposite from the only substituent on the ring, so it makes sense that it has a shift value around 7 ppm. It is unclear why it is reported as a doublet, since it has two hydrogen neighbors that it could easily couple with, leading us to predict that it would appear as a triplet.
6.21	d	1H	M	This hydrogen is located one carbon away from an electron-withdrawing carbonyl group, so its shift is relatively high. It appears as a doublet because it couples with the hydrogen on the neighboring carbon on the same ring.
5.93	d	1H	L	This hydrogen is located on an aromatic ring, giving it a relatively high shift. It is more deshielded than the other hydrogen on the same ring because it is attached to only one electron-donating oxygen. It appears as a singlet because it has no hydrogen neighbors close enough to couple with.
5.86	d	1H	K	This hydrogen, although located on an aromatic ring, is attached to two electron-donating oxygens, making it less deshielded than other aromatic hydrogens. It appears as a singlet because it has no hydrogen neighbors close enough to couple with.
4.99/4.38	d	1H each	J/H	These diastereotopic hydrogens appear as two separate peaks with the same coupling constant. They are located between an aromatic ring and an oxygen, making them relatively deshielded. The most likely explanation for their different shift values is that one of them interacts significantly more with the oxygen on the five-membered ring than the other due to steric factors.
4.39/4.32	d	1H each	I/G	These diastereotopic hydrogens appear as two separate peaks. They are more shielded than the hydrogens on the other side of the oxygen because they are located farther from the phenyl ring. They are doublets because there are no hydrtogen neighbors close enough to couple with.
3.80	s	3H	F	These hydrogens do not appear on the molecule; it is possible that some of the solvent (methanol) remained in the product when the NMR was conducted.
3.72	s	3H	E	These hydrogens are relatively shielded because they are located right next to an electron-donating oxygen. They are singlets because there are no three-bond neighbor hydrogens.
3.31/3.27	d	1H each	D/C	These diastereotopic hydrogens are relatively shielded due to their proximity to the two oxygens. They are doublets because they couple with each other.
0.98/0.99	s	3H each	A/B	These six hydrogens are located on two diastereotopic methyl groups. They are the most shielded on the molecule because of their distance from any electron-withdrawing groups.

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