Final answer:
The NMR spectrum of cyclohex-3-enecarboxylic acid methyl ester is characterized by both ¹H NMR and HMBC NMR techniques. These methods provide information on the hydrogen environment and long-range correlations between hydrogen and carbon atoms.
Step-by-step explanation:
The student is asking about the characterization of the NMR spectrum of cyclohex-3-enecarboxylic acid methyl ester. The options provided are different types of NMR (Nuclear Magnetic Resonance) techniques: ¹H NMR (Proton NMR), ¹³C NMR (Carbon-13 NMR), COSY NMR (Correlation Spectroscopy), and HMBC NMR (Heteronuclear Multiple Bond Correlation).
¹H NMR and ¹³C NMR are the most commonly used NMR techniques to determine the structure of organic molecules. ¹H-NMR provides information about the number and types of hydrogen atoms in a molecule, their environment, and how they are connected. ¹³C-NMR provides information about the carbon skeleton of a molecule. COSY NMR is a two-dimensional NMR technique that can help determine which hydrogens are adjacent to each other, while HMBC NMR is another two-dimensional technique that can show correlations between hydrogen and carbon atoms that are not directly bonded, but are separated by two or three bonds.
Based on the information given in the support section, the structure of cyclohex-3-enecarboxylic acid methyl ester was confirmed using ¹H-NMR, ESI-MS, and HMBC NMR. Therefore, both ¹H NMR and HMBC NMR play crucial roles in characterizing the NMR spectrum of this compound.