Interview Question in Frequency Spectrum
Interview Question :: Organic Chemistry Help Part 2
4. In the determination of the NMR spectra of ultra-pure 2-phenyl-1-ethanol; four signals were generated: one signal was a broad signal stretching from 7.3 to 6.9 ppm, which on better resolution in a higher radio frequency NMR spectrophotometer showed this signal to actually be three signals of integrated peak heights of 2:1:2 ratio, respectively; a triplet (symmetric, J = 7 Hz) at 2.3 ppm; a quartet, almost symmetric, at 2.9 ppm; and a symmetric triplet (J=7 Hz) at 2.0 ppm. When a drop pf sulfuric acid was added to the sample, one of the signals simplified to a broadened singlet that moved to 3.5 ppm. Which signal did this?
A) The signal at 6.9 to 7.3 ppm
B) The signal at 2.9 ppm
C) The signal at 2.3 ppm
D) The signal at 2.0 ppm
5. Prove a structure that is consistent with the data below.
C7H16O
IR (cm-1): 3200-3600 (broad), 2950
1H NMR (d): 2.8 (1H, broad s), 1.0 (6H, s), 0.9 (9H, s)
13C NMR (d): 68 (s), 39 (s), 16 (q), 13 (q)
Loading ...
Advertisement2