Identify the structure of a compound with the molecular formula C9H10O that exhibits the following H NMR spectrum
The correct answer and explanation is :
To identify the structure of a compound with the molecular formula C9H10O that exhibits a specific proton NMR spectrum, I would need to know the details of the proton NMR (H NMR) spectrum itself. However, based on the given molecular formula (C9H10O), there are a few possible structures that can fit the formula. Here is how we would approach the analysis of such a compound based on typical NMR data:
Step 1: Analyze the Molecular Formula
The molecular formula, C9H10O, suggests that the compound consists of 9 carbon atoms, 10 hydrogen atoms, and 1 oxygen atom. This can indicate the presence of a benzene ring (since C6H5 is a common fragment in organic compounds), with additional substituents contributing to the remaining carbons, hydrogens, and the oxygen atom.
Step 2: Understand Key Features from H NMR
In an H NMR spectrum, protons (hydrogens) in different chemical environments will produce signals at different chemical shifts (δ values). The splitting of these signals, known as coupling, gives additional information about the number of neighboring protons.
Step 3: Consider Possible Structures
Given the molecular formula and typical data from proton NMR, one possible structure could be phenylethanol (C6H5CH2OH), which consists of a benzene ring (C6H5) attached to a -CH2OH group.
In the H NMR spectrum of phenylethanol, you might observe:
- A doublet (around 7-8 ppm) due to the aromatic protons on the benzene ring (typically 2-3 protons). These protons couple with each other and split into a doublet pattern.
- A triplet (around 2.5-3.0 ppm) for the -CH2- group attached to the benzene ring, with 2 hydrogens. This signal is typically split into a triplet due to coupling with the neighboring -CH2OH group.
- A broad singlet (around 4.5-5.5 ppm) for the -OH proton of the alcohol (-OH), which appears as a broad singlet due to hydrogen bonding.
Step 4: Verify with Integration and Splitting Patterns
The integration of the peaks in the H NMR spectrum should match the number of hydrogens in each environment (i.e., the singlet, triplet, and doublet). The splitting patterns (doublet, triplet, singlet) should correspond to the coupling between protons, and the chemical shifts should fall within expected ranges.
In conclusion, phenylethanol is a plausible structure for the compound with the molecular formula C9H10O, which fits the expected proton NMR features for aromatic, methylene, and alcohol protons.