A research student who had just commenced a PhD found on his / her newly acquired bench a container with two labels on it: 4-methyphenol and 4-methylaniline. His / her (ever-enthusiastic) supervisor suggested reacting the "unknown' compound with acetyl chloride (CH3COCI) and running an IR spectrum of the resultant product as one method of determining which of the two labels was indeed correct. The spectrum recorded is shown in Fig. 1. Explain, with reasoning, which of the two labels is the correct one. 80 75 70 65 60 35 50 40 35 30 25 20 15 10 5 0.0 40000 3094.45 3277.94 3300 2000 2400 2000 1800 1398 1600 132 1400 102 12110 11792 1006 30 000 111366 1000 865 849.28 B 60192 69758 331.93 44100 496.76

A research student who had just commenced a PhD found on his / her newly acquired bench a container with two labels on it: 4-methyphenol and 4-methylaniline. His / her (ever-enthusiastic) supervisor suggested reacting the "unknown' compound with acetyl chloride (CH3COCI) and running an IR spectrum of the resultant product as one method of determining which of the two labels was indeed correct. The spectrum recorded is shown in Fig. 1. Explain, with reasoning, which of the two labels is the correct one. 80 75 70 65 60 35 50 40 35 30 25 20 15 10 5 0.0 40000 3094.45 3277.94 3300 2000 2400 2000 1800 1398 1600 132 1400 102 12110 11792 1006 30 000 111366 1000 865 849.28 B 60192 69758 331.93 44100 496.76

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

Chapter20: Dienes, Conjugated Systems, And Pericyclic Reactions

Section20.3: Uv-visible Spectroscopy

Problem 20.5P

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