Based on the data provided, propose the structures of the structural isomers A and B.
a. When the sample is shaken with D2O (isomer A), the singlet at 1.5 ppm disappears from the NMR spectrum. Similarly, the singlet at 3.3 ppm in the B spectrum vanishes when shaken with D2O (isomer B). The IR spectrum, on the other hand, revealed two peaks at 3300 cm-1 for A and only one peak at 3300 cm-1 for B.
b. The mass spectrum shows a molecular ion peak at m/z 101 corresponds for both, as well as a prominent peak at m/z 72 for A and m/z 86 for B. Show which cleavage is responsible for these peaks.
For isomer A For Isomer B
![](https://lightcat-files.s3.amazonaws.com/problem_images/8f743f45e82c8be4-1670522442790.jpg)
![](https://lightcat-files.s3.amazonaws.com/problem_images/32f6305a610cf6de-1670522466417.jpg)