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Consider the data for an unknown compound with the molecular formula C9H10O3. IR: 2400–3200 cm−1, 1700 cm−1, 1630 cm−1 1H NMR: 1.53 (3H, t, =8 Hz); 4.32 (2H, q, =8 Hz); 7.08, 8.13 (4H, pair of leaning doublets, =10 Hz); 10 (1H, broad, disappears with D2O shake). Deduce the structure.

User Gabriele
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Final answer:

The molecular formula of the unknown compound C9H10O3 can be deduced by analyzing the IR and H NMR spectra. The IR spectrum shows peaks indicative of C-H stretch, carbonyl group (C=O), and conjugated carbonyl group (C=C=O). The H NMR spectrum reveals the presence of alkyl and aryl groups, as well as a hydroxyl group that disappears upon shaking with D2O.

Step-by-step explanation:

The molecular formula of the unknown compound is C9H10O3. From the given data, we can deduce its structure by analyzing the IR and H NMR spectra.

The IR spectrum shows peaks at 2400-3200 cm⁻¹, 1700 cm⁻¹, and 1630 cm⁻¹, indicating the presence of a C-H stretch, a carbonyl group (C=O), and a conjugated carbonyl group (C=C=O).

The H NMR spectrum provides the following information: 1.53 (3H, t, J = 8 Hz), 4.32 (2H, q, J = 8 Hz), 7.08, 8.13 (4H, pair of leaning doublets, J = 10 Hz), 10 (1H, broad, disappears with D2O shake).

From the H NMR spectrum, we can identify the following functional groups: an alkyl group (1.53 ppm), an alkyl group attached to a hydrogen-bonded proton (4.32 ppm), and two aryl groups (7.08 and 8.13 ppm). The broad peak at 10 ppm indicates the presence of a hydroxyl group (OH) that disappears upon shaking with D2O.

User Aramil Rey
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