Q13-34E - Organic Chemistry (Mcmurry)

Question

How many types of non-equivalent protons are present in each of the following molecules?

Step-by-Step Solution

Answer

1. 4
2. 4
3. 2
4. 6
5. 5

Step 1: Non-Equivalent proton

The proton which is having a different environment and all protons give different peaks is the non-equivalent proton whereas if the proton shares the same environment and all protons gave the same singles or peaks are the equivalent protons.

Step 2: Non-Equivalent proton in compound a

As you see in the compound both the methyl substituents share same environment so their 6 H produce the same 1 signal

And the 2 carbon 4 hydrogen produce 1 signal similarly, 3 carbon 4 hydrogen produce 1 signal last 4 carbon produce 1 signal.

Hence, a total 4 equivalent protons are present as shown:

Step 3: Non-Equivalent proton in compound b

As u see in the compound methyl group with O atom form 1 signal

Then methylene from 1 signal that 1 equivalent proton

Again the 2^nd methylene from 1 signal that 1 equivalent proton

The methyl with the methylene form1equivalent proton

Hence, a total 4 equivalent protons are present as shown:

Compound A

Step 4: Non-Equivalent proton in compound c

As you, u seen in the compound the head which is marked by 1 is having the same environment so 1 signal and 1 equivalent proton and all the side carbon marked by 2 produce 1 signal so,

A total 2 equivalent protons are present as shown:

Compound A

Step 5: Non-Equivalent proton in compound d

As you see on the compound the proton represented by1 produce 1 signal and the proton around the alkene both share a different environment represented by 2 and 3 produce a different signal and then carbon represented by 4 produce signal and then 2 carbon represent by 5 having the same environment produce the same signal then carbon 6 produce 1 more different signal so,

A total 6 equivalent protons are present as shown:

Compound D

Step 6: Non-Equivalent proton in compound e

As you see in the compound the 3 protons are surrounded by alkene represented by 1, 2, 3 having different environments produce different signals then the methylene group produces a signal represented by 4 then the methyl group represented by 5.

So, a Total of 5 equivalent protons is present as shown:

Compound E