I know you are unable to draw things on this website, but I am in desperate need for help and was wondering if someone would be able to guide or help me.
I need to draw and assign the expected proton NMR spectra for the following compounds and show splitting.
since you can't draw, I was wondering if you could check over where my peaks are and if there is splitting.
1. 2,5-dimethyl-2,4-hexadiene
I had three unique H's
6-H singlet at 1.2
6-H singlet at 1.5
and 2-H doublet at 5.5
2. 1-phenyl-2-methylpropane
I had four unique H
6-H doublet at 1.5
1-H with 7 splits at 1.6
2-H doublet at 2.5
and 5-H singlet at 7.5
3. CH3N(CH2CH3)2
I had two unique H
6-H triplet at 1.5
7-H with 4 splits at 2.3
THANK YOU SO MUCH, any help is greatly appreciated
I apologize for the inconvenience, but as an AI text-based bot, I am unable to directly visualize or check peaks on any spectra. However, I can assist you in understanding the general approach to determining and interpreting proton NMR spectra.
Proton NMR spectroscopy measures the interaction between the nucleus of a hydrogen atom (proton) and an external magnetic field. When protons in a molecule experience different local environments due to chemical shifts, they produce distinct peaks on the spectrum, while coupling with neighboring protons leads to splitting patterns.
It seems like you have attempted to assign the expected proton NMR spectra for the three compounds. I will give you guidance on how to determine the chemical shifts and splitting patterns for the given compounds.
1. 2,5-dimethyl-2,4-hexadiene:
- You mentioned having three unique hydrogens: 6-H (singlet) at 1.2 ppm, 6-H (singlet) at 1.5 ppm, and 2-H (doublet) at 5.5 ppm.
- Chemical shifts (ppm) are influenced by nearby functional groups and electronic effects. The singlet at 1.2 and 1.5 ppm suggests these hydrogens are in a similar environment (likely methyl groups) and are shielded by their surroundings. The doublet at 5.5 ppm indicates coupling with a neighboring hydrogen, resulting in a splitting pattern.
- Based on this information, you can expect three peaks: two singlets (1.2 ppm and 1.5 ppm) for the methyl groups, and one doublet (around 5.5 ppm) for the hydrogen adjacent to the double bond.
2. 1-phenyl-2-methylpropane:
- You mentioned having four unique hydrogens: 6-H (doublet) at 1.5 ppm, 1-H (with 7 splits) at 1.6 ppm, 2-H (doublet) at 2.5 ppm, and 5-H (singlet) at 7.5 ppm.
- The 6-H and 2-H (doublets) indicate coupling with a single neighboring hydrogen, producing a splitting pattern.
- The 1-H (with 7 splits) likely corresponds to the hydrogen on the phenyl (aromatic) ring. Because it is ortho to the methyl group, it experiences coupling with three adjacent hydrogens (ortho coupling) and shows seven peaks in total (1:3:3 pattern).
- The 5-H (singlet) at 7.5 ppm corresponds to the hydrogen on the aromatic ring that is farthest away from the methyl group.
- Based on this information, you can expect four peaks: two doublets (1.5 ppm and 2.5 ppm), one heptet (1.6 ppm), and one singlet (7.5 ppm).
3. CH3N(CH2CH3)2 (N,N-diethylmethanamine):
- You mentioned having two unique hydrogens: 6-H (triplet) at 1.5 ppm and 7-H (with 4 splits) at 2.3 ppm.
- The 6-H (triplet) at 1.5 ppm suggests coupling with two adjacent hydrogens.
- The 7-H (with 4 splits) indicates coupling with three hydrogens: two hydrogens adjacent to the nitrogen atom (ortho coupling) and one hydrogen on the nitrogen itself.
- Based on this information, you can expect two peaks: one triplet (1.5 ppm) and one quartet (2.3 ppm).
Please note that actual chemical shifts and splitting patterns may vary depending on the specific experimental conditions. It is always a good idea to consult reference sources or use specialized software or databases for more precise predictions.
I hope this explanation helps you in assigning the expected proton NMR spectra. If you have any further questions or need additional assistance, feel free to ask.