The following spectroscopic data are for two carbonyl compounds with the formula

Chapter 17, Problem 27

(choose chapter or problem)

The following spectroscopic data are for two carbonyl compounds with the formula C8H12O. Suggest a structure for each compound. The letter “m” stands for the appearance of this particular part of the spectrum as an uninterpretable multiplet.

(a) \({ }^{1} \mathrm{H} \text { NMR: } \delta=1.60(\mathrm{~m}, 4 \mathrm{H}), 2.15(\mathrm{~s}, 3 \mathrm{H}) \text {, }\) \(2.19(\mathrm{~m}, 4 \mathrm{H}) \text {, and } 6.78(\mathrm{t}, 1 \mathrm{H}) \mathrm{ppm} .{ }^{13} \mathrm{C} \text { NMR: } \delta=21.8,22.2,23.2,25.0,26.2,139.8,140.7 \text {, }\) and \(198.6 \mathrm{ppm}\)

(b) \({ }^{1} \mathrm{H} \text { NMR: } \delta=0.94(\mathrm{t}, 3 \mathrm{H}), 1.48(\operatorname{sex}, 2 \mathrm{H}), 2.21(\mathrm{q}, 2 \mathrm{H}), 5.8-7.1\) \((\mathrm{m}, 4 \mathrm{H}) \text {, and } 9.56(\mathrm{~d}, 1 \mathrm{H}) \mathrm{ppm} .{ }^{13} \mathrm{C} \text { NMR: } \delta=13.6,21.9,35.2,129.0,135.2,146.7,152.5 \text {, }\) \(\text { and } 193.2 \mathrm{ppm} \text {. }\)