9. (a) A compound with chemical formula C₂H₂CIBr shows the proton NMR spectrum consisting of two doublets with J-7.3 Hz. What is the molecular structure of this compound? (b) The proton chemical shifts of the two doublets from the previous question differ by 0.3 ppm. Can you consider the proton spectrum as the first order one?

9. (a) A compound with chemical formula C₂H₂CIBr shows the proton NMR spectrum consisting of two doublets with J-7.3 Hz. What is the molecular structure of this compound? (b) The proton chemical shifts of the two doublets from the previous question differ by 0.3 ppm. Can you consider the proton spectrum as the first order one?

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter14: Mass Spectrometry

Section: Chapter Questions

Problem 14.26P: Following is the mass spectrum of bromocyclopentane. The molecular ion m/z 148 is of such low...

See similar textbooks

Similar questions

In a 300 MHz NMR spectrometer, A) what is the Larmor frequency in MHz of a 15N nucleus? g H = N 26.752; g = 2.7126; B) Using the same NMR instrument, suppose that a 13C nucleus from a sample generates a signal which has a frequency of 11,250 Hz higher than that from the carbons in TMS. What is the chemical shift of that carbon atom from the sample? A) 30 MHz; B) 0.15 ppm OA) 25 MHz; B) 0.35 ppm A) 35 MHz; B) 0.30 ppm OA) 25 MHz; B) 0.55 ppm
Please look at the Proton NMR spectrum and identify the proposed molecular structure.
The organic compound 1,4-dimethylbenzene (also known as p-xylene) has the formula (CH3)2C6H4. Its structure has two CH3 (methyl) groups substituted at opposite positions on the benzene (C6H6) ring. Predict the number of peaks in the low-resolution proton NMR spectrum of this compound and the relative areas of the peaks.
Sketch the form of an A3M2X4 spectrum, where A, M, and X are protons with distinctly different chemical shifts and JAM > JAX > JMX ·
(a) Calculate the energy difference between the two spin states of 1H and of 13C in a magnetic field of 6.8 T. 1H 4.0 1.19e-25 X J 13C 4.0 J (b) What is the precession frequency of a 1H nucleus at this magnetic field? Of a 13C nucleus? 1H 4.0 290 MHz 13C 4.0 73 MHz (c) At what magnetic field do protons precess at a frequency of 300. MHz? 4.0 7.04 T
(a) What would be the chemical shift of a peak that is observed at 655.2 Hz from the reference tetramethylsilane (TMS) recorded using a 90 MHz spectrometer ? (b) At what frequency would the chemical shift of chloroform (CHCl3, δ = 7.28 ppm) occur relative to TMS on a spectrum recorded on a 300 MHz spectrometer? (c) At what frequency and chemical shift would the signal for chloroform occur when using a 1 GHz NMR spectrometer?
(a) Draw all six isomers of formula C4H8 (including stereoisomers).(b) For each structure, show how many types of H would appear in the proton NMR spectrum.(c) For each structure, show how many types of C would appear in the 13C NMR spectrum.
13C(1h) what is bracket mean in this case? is that mean carbon nmr proton nmr in same time?
Describe the 1H-NMR spectrum of 4-bromoaniline (chemical shift, integration, multiple). Make a table and describe the results.
A carbon signal measured in a 300MHz spectrometer with an observing frequency of 75.47MHz is found to have a chemical shift of 187.23 ppm. What is the resonance frequency of the carbon with this chemical shift?
What effect does increasing the operating frequency of a 1H NMR spectrum have on each value: (a) the chemical shift in δ; (b) the frequency of an absorption in Hz; (c) the magnitude of a coupling constant J in Hz?
Shown below is the Proton NMR of a hydrocarbon of the formula C11H16. Given the number of hydrogen atoms represented by each of the 3 integrals, what is the structure of the compound?