Concept explainers
Interpretation:
Which of the compounds
Concept introduction:
IR spectroscopy enables to identify different
One of the greatest advantages of IR spectroscopy is that the frequency of a particular type of vibration is typically found within a characteristic range of frequencies, regardless of the functional group with which the vibration is associated. The fact that absorptions by certain vibrations appear with characteristic frequency ranges enables us to use IR spectroscopy to obtain structural information about a molecule. The
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Organic Chemistry: Principles and Mechanisms (Second Edition)
- Compound 1 has molecular formula C6H12. It shows three signals in the 1H-NMR spectrum, one at 0.96 ppm, one at 2.03 ppm, and one at 5.33 ppm. The relative integrals of these three signals are 3, 2, and 1, respectively. Compound 2 has molecular formula C7H15Br. It shows two signals in the 1H-NMR spectrum, one at 1.08 ppm and one at 1.59 ppm. The relative integrals of these two signals are 3 and 2, respectively. Propose structures for compounds 1 and 2, explaining how you reach your conclusion.arrow_forward||| An unknown has the formula C H₂O. The IR spectrum of this substance has a strong vibration near 1700 cm-¹. Which structure below is consistent with these data? OH || IV -OH A) I B) II C) III D) IVarrow_forwardThe simulated APT spectrum of a compound with the molecular formula C5H11 is shown. Draw a structure that is consistent with this data.arrow_forward
- Based on the spectra you located, does your molecule have a carbonyl? If so, what functional group is it a part of (carboxylic acid, ketone, aldehyde, ester, amide) and what is the frequency (in wavenumbers) of the absorption peak? If not, what is the approximate frequency range for a carbonyl? Does your molecule have either an –O-H or –N-H bond? If so, what functional group is it a part of (carboxylic acid, alcohol, amine, amide) and what is the frequency (in wavenumbers) of the absorption peak? If not, what are the approximate frequency ranges for an –O-H and an –N-H bond? Does your molecule have either an alkyne or nitrile functional group? If so, which functional group is it and what is the frequency (in wavenumbers) of the absorption peak? If not, what is the approximate frequency range for a triple bond?arrow_forwardExplain why these are the correct spectra for the molecules. Identify a specific absorption band which identifies each characteristic functional group of the molecule chosen.arrow_forwardA'2 The 'H-NMR spectra of cyclohexanol and cyclohexanone are given below. Identify which spectrum belongs to which compound and assign the peaks in each spectrum that substantiate your decision.arrow_forward
- 125 ppm 138 ppm 153 ppm 130 ppm The chemical shifts of two carbon atoms are given for the molecules shown here. It appears that the addition of the OH group increases the chemical shift of the C atom to which it is attached, but that it decreases the chemical shift of the C atom on the opposite side. How do you account for these observations? Hint: Draw all of the pertinent resonance structures. CH3 Но -CH3arrow_forwardBelow are three MS spectra, Spectra 1, 2, and 3. Each of this mass spectrum corresponds to either Compound A (contains one Cl in the molecular formula), Compound B (one I in the molecular formula), and Compound C (one Br in the molecular formula). Identify which spectra corresponds to which compound. Provide explanations for your choices.arrow_forwardQ3. The following spectra belongs to either benzoic anhydride, aniline and phenol. Identify and describe the important absorption in the spectral data shown below. 4000 3440 1979 1 217 3310 9 1000 19 1979 1 3460 44 2906 06 3396 58 2630 84 320984 1918 1 30954 72 OL FLOE 1340 06 1325 79 1300 79 1276 20 103900 182605 1174 47 106904 1028 72 10 966 616 64 640 1 86 929 3041 32 1500 4 115499 2013 00 1400 60 1117 79 C0031 a PIR 1000 Wild PUBERGH 1500 1000 100 Whearrow_forward
- Explain why this is the correct spectra for these molecules. Identify a specific absorption band which identifies each characteristic functional group of the chosen molecule.arrow_forwardFor the following compound how many different signals would you see in the carbon NMR? (Assume that you can see them all.) 4 O 5 O 3 09 CO |arrow_forwardmolecular formula: C5H9N 1. Given the molecular formula, label important peaks on the spectrum and explain how you determined the Structural Formula for your assigned compound.arrow_forward
- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning