Question V. Below you will find combined spectra of compounds; propose in each case a structure consistent with the information provided. Explain how the proposed structure responds in each case to the information of each spectrum. (GO, MS, NMR). For mass spectra, indicate the formation of the fragment that gives rise to the base peak and other major peaks. I. ll. lll. ​​​​​​​ II. MASS SPECTRUM INFRARED SPECTRUM NMR SPECTRUM

VZJMML The Asker · Chemistry

V. Below you will find combined spectra of compounds; propose in each case a structure consistent with the information provided. Explain how the proposed structure responds in each case to the information of each spectrum. (GO, MS, NMR). For mass spectra, indicate the formation of the fragment that gives rise to the base peak and other major peaks.

I.

ll.

lll.

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Transcribed Image Text: II. MASS SPECTRUM INFRARED SPECTRUM NMR SPECTRUM
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Transcribed Image Text: II. MASS SPECTRUM INFRARED SPECTRUM NMR SPECTRUM
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&#12304;General guidance&#12305;The answer provided below has been developed in a clear step by step manner.Step1/3I. The compound is 1-phenylpropan-2-one.In IR spectrum, a sharp peak at 1720 cm-1 corresponds to C=O stretching of the ketone group.Mass fragmentation is shown here.O<path d=" M 330 170 L 370 170 " marker-end="url(#KYkteOgp7xoBQZ4w4m8vs-end-arrowhead)" fill="#FFFFFF" stroke="rgb(51, 51, 51)" stroke-width="2" stroke-dasharray="0" stroke-linecap="round" stroke-linejoin="round" stroke-miterlimit="10" dominant-baseline="text-before-edge" vector-effect="non-scaling-stroke" data-id="KYkteOgp7xoBQZ4w4m8vs">+m/z 134m/z 91Explanation:Alpha cleavage adjacent to ketone group gives fragment with m/z 91 which is a base peak.Proton assignment for NMR spectrum is given belowO{abcExplanation:In NMR spectrum, five aromatic protons 'a' give multiplet at 7.2 ppm. Benzylic protons 'b' appear as singlet at 3.7 ppm and methyl protons 'c' give singlet at 2.1 ppm.Explanation:Please refer to solution in this step.Step2/3II. The compound is ethyl propionate.In IR spectrum, a sharp peak at 1730 cm-1 is due to C=O stretching of an ester group. The C-O stretching is seen at 1200 cm-1.The mass fragmentation of the molecule is shown below.OO<path d=" M 310 160 L 350 160 " marker-end="url(#6KjMwifRhy6XEWVONBkx9-end-arrowhead)" fill="#FFFFFF" stroke="rgb(51, 51, 51)" stroke-width="2" stroke-dasharray="0" stroke-linecap="round" stroke-linejoin="round" stroke-miterlimit="10" dominant-bas ... See the full answer