20) An unknown compound has the chemical formula CH₂O. It's IR spectrum and ¹H NMRspectrum are shown below. Propose a structure for the unknown molecule. Calculate theDegrees of Unsaturation (DU), assign any important peaks in the IR spectrum to vibrationalmodes and briefly explain why the structure fits the 'H NMR spectrum that is providedDegrees of unsaturation (show work below):442Du= (2(3)+2)-62-8-16 - 2²/2/2 = 134371739Amply0Vibrational Assignments of IR PeaksWavenumber (cm-¹) Vibrational Assignment0-4 stretch6=0 strekhPeak 1:9.79 ppm14Singlet38Brief rationalization for proposed structure: (explain why DU, IR, andNMR are consistent with proposed structure)ppmPeak 22.45 ppm2HQuartetPeak 31.11 ppm3HTripletDProposed structure of unknown:

Degree of unsaturation (Du) = (2C + 2 + N - H - X)/2 Where, C = number of carbon atoms; N = number…

20) An unknown compound has the chemical formula CH₂O. It's IR spectrum and H NMR spectrum are shown below. Propose a structure for the unknown molecule. Calculate the Degrees of Unsaturation (DU), assign any important peaks in the IR spectrum to vibrational modes and briefly explain why the structure fits the 'H NMR spectrum that is provided Degrees of unsaturation (show work below): 642 Du = (2(3)+2)-6-8-6-2²/1/2 = 1 2 3437 1739 16-o mpy m Vibrational Assignments of IR Peaks Wavenumber (cm-¹) Vibrational Assignment 2 0-4 stretch C=0 strekn Peak 1: 9.79 ppm 1H Singlet 9 8 Brief rationalization for proposed structure: (explain why DU, IR, and NMR are consistent with proposed structure) ppm Peak 2 2.45 ppm 2H Quartet Peak 3 1.11 ppm 3H Triplet Proposed structure of unknown:

20) An unknown compound has the chemical formula CH₂O. It's IR spectrum and H NMR spectrum are shown below. Propose a structure for the unknown molecule. Calculate the Degrees of Unsaturation (DU), assign any important peaks in the IR spectrum to vibrational modes and briefly explain why the structure fits the 'H NMR spectrum that is provided Degrees of unsaturation (show work below): 642 Du = (2(3)+2)-6-8-6-2²/1/2 = 1 2 3437 1739 16-o mpy m Vibrational Assignments of IR Peaks Wavenumber (cm-¹) Vibrational Assignment 2 0-4 stretch C=0 strekn Peak 1: 9.79 ppm 1H Singlet 9 8 Brief rationalization for proposed structure: (explain why DU, IR, and NMR are consistent with proposed structure) ppm Peak 2 2.45 ppm 2H Quartet Peak 3 1.11 ppm 3H Triplet Proposed structure of unknown:

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

Chapter21: Benzene And The Concept Of Aromaticity

Section: Chapter Questions

Problem 21.20P

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