Question

How many unique 1h nmr and 13c nmr signals exist for each compound?

Answer 1

The structures along with their codes are given below.

For Compound A:

# of ¹H signals: 3 (as both side chains from carbonyl positions are same)
# of ¹³C signals: 4 

For Compound B:

# of ¹H signals: 3 (the two methyl groups of isopropyl are equivalent)
# of ¹³C signals: 4

For Compound C:
# of ¹H signals: 2 (as both side chains from carbonyl positions are same)
# of ¹³C signals: 3

For Compound D:
# of ¹H signals: 3
# of ¹³C signals: 4