4. a. The ¹H NMR spectrum of a compound with the molecular formula CsH10O2 is shown below (integral values are given above each set of peaks). Analysis of its ¹3C NMR spectrum shows peaks at 174, 61, 27, 14 and 9 ppm (see the posted lecture notes for June 7 for some guidance on ¹³C NMR spectroscopy). The IR spectrum shows a prominent peak at 1735 cm™¹ and no peaks with a stretching frequency above 3000 cm³¹. What is the structure of this compound? 3.0 b. Which peak in the NMR spectrum in part a corresponds to a CH₂ group (called a "methylene") bonded to an O atom? b. 1.25 ppm c. 2.31 ppm a. 1.12 ppm e. There are no CH2 groups bonded to an O atom in this compound. d. 4.12 ppm 1.0 PPM

4. a. The ¹H NMR spectrum of a compound with the molecular formula CsH10O2 is shown below (integral values are given above each set of peaks). Analysis of its ¹3C NMR spectrum shows peaks at 174, 61, 27, 14 and 9 ppm (see the posted lecture notes for June 7 for some guidance on ¹³C NMR spectroscopy). The IR spectrum shows a prominent peak at 1735 cm™¹ and no peaks with a stretching frequency above 3000 cm³¹. What is the structure of this compound? 3.0 b. Which peak in the NMR spectrum in part a corresponds to a CH₂ group (called a "methylene") bonded to an O atom? b. 1.25 ppm c. 2.31 ppm a. 1.12 ppm e. There are no CH2 groups bonded to an O atom in this compound. d. 4.12 ppm 1.0 PPM

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter13: Structure Determination: Nuclear Magnetic Resonance Spectroscopy

Section13.SE: Something Extra

Problem 60GP: Compound A, a hydrocarbon with M+=96 in its mass spectrum, has the 13C spectral data given below. On...

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