Concept #1: Building Molecular Sentences
Example #1: Building a molecular sentence
Practice: Propose a structure for the following compound that fits the following 1H NMR data:
Formula: C3H8O2 1H NMR: 3.36 δ (6H, singlet)
4.57 δ (2H, singlet)
Practice: Propose a structure for the following compound that fits the following 1H NMR data:
Formula: C2H4O2 1H NMR: 2.1 δ (singlet, 1.2 cm)
11.5 δ (0.5 cm, D2O exchange)
Practice: Propose a structure for the following compound that fits the following 1H NMR data:
Formula: C10H14 1H NMR: 1.2 ppm (6H, doublet)
2.3 ppm (3H, singlet)
2.9 ppm (1H, septet)
7.0 ppm (4H, doublet)
Practice: Propose a structure for the following compound, C7H12O2 with the given 13C NMR spectral data:
Broadband decoupled 13C NMR: 19.1, 28.0, 70.5, 129.0, 129.8, 165.78 δ
DEPT-90: 28.0, 129.8 δ
DEPT-135: 19.1 δ (↑), 28.0 (↑) , 129.8 δ (↑) , 70.5 δ (↓)&129.0δ (↓)
Practice: Propose a structure for the following compound, C5H10O with the given 13C NMR spectral data:
Fully Broadband decoupled 13C NMR and DEPT: 206.0 δ (↑); 55.0 δ (↑); 21.0 δ (↓)& 11.0 δ (↑).
Practice: Provide the structure of the unknown compound from the given information.
Formula: C4H10O IR: 3200-3600 cm-1 1H NMR: 0.9 ppm (6H, doublet)
1.8 ppm (1H, nonatet)
2.4 ppm (1H, singlet)
3.3 ppm (2H, doublet)
Practice: Provide the structure of the unknown compound from the given information.
Formula: C4H9N IR: 2950 cm-1, 3400 cm-1 1H NMR: 1.0 ppm (4H, triplet)
2.1 ppm (4H, triplet)
3.2 ppm (1H, singlet)