Concept explainers
Interpretation:
A structure for the compound B (an isomer of A in the problem 19-81) with the following descriptions is to be proposed.
IR: 1730 cm-1; 1HNMR: 2.75 δ (Rel.area=2.00), 2.95 δ (Rel.area=2.00), 7.23 δ (Rel.area=3.00), 7.31 δ (Rel.area=2.00), 9.82 δ (Rel.area=1.00).
Concept introduction:
In 1HNMR the aldehyde protons absorb near 10 δ with a coupling constant, J=3Hz. Hydrogens on the carbon next to aldehyde group absorb near 2.0-2.3 δ. Methyl ketones show a sharp three proton singlet near 2.1 δ.
To propose:
A structure for the compound B (an isomer of A in the problem 19-81) with the following descriptions is to be proposed.
IR: 1730 cm-1; 1HNMR: 2.75 δ (Rel.area=2.00), 2.95 δ (Rel.area=2.00), 7.23 δ (Rel.area=3.00), 7.31 δ (Rel.area=2.00), 9.82 δ (Rel.area=1.00).
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Organic Chemistry
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