The structure of compound A is to be identified and two peaks in the mass spectrum are to be rationalized. Concept Introduction: In the IR spectroscopy, change in the dipole moment produces absorption of energy. All the functional groups have different absorption frequency based on which they can be differentiated. For carbonyl C=O group, the absorption takes place at 1725 c m -1 which is different for carboxylic acid and esters. In proton NMR, the proton resonance is taken into consideration for different functional groups. Due to change in surroundings of the proton, the chemical shift changes.

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Chapter 20, Problem 20.60AP

Interpretation Introduction

Interpretation:

The structure of compound A is to be identified and two peaks in the mass spectrum are to be rationalized.

Concept Introduction:

In the IR spectroscopy, change in the dipole moment produces absorption of energy. All the functional groups have different absorption frequency based on which they can be differentiated. For carbonyl C=O group, the absorption takes place at 1725 cm-1 which is different for carboxylic acid and esters. In proton NMR, the proton resonance is taken into consideration for different functional groups. Due to change in surroundings of the proton, the chemical shift changes.

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