Organic Chemistry 1 · Proton NMR reasoning
Find the compound with a septet
Conditions: Spectrum: doublet (6H) and septet (1H) plus an aromatic multiplet.
Draw this problem yourself
Drag from the electrons that move to where they go, or tap one and then the other. Every arrow is checked; Hint helps when you're stuck. No account needed.
The question
Which structure gives a 6H doublet and a 1H septet besides its aromatic signals?
Reveal the answer and explanation
Answer and explanation
Correct answer Isopropylbenzene
CH(CH3)2: CH is a septet, the 6H is a doublet.
Not this one Propylbenzene
Gives a 3H triplet, a 2H sextet and a 2H triplet.
Not this one tert-Butylbenzene
The 9H appear as a singlet; no neighbours.
Not this one Ethylbenzene
Gives a 3H triplet and a 2H quartet.
Worked solution
A septet means 6 neighbouring H (n+1 = 7) and a 6H doublet means two equivalent CH3 each beside one H: an isopropyl group, as in cumene.
What you'll practice
Use the n+1 rule to pick the structure giving a septet and a doublet.
You just pushed every arrow of this one.
Every one of the 5349 Orgo 1 and Orgo 2 problems works like this: feedback on each arrow, hints when you're stuck, a no-hint quiz mode. Free with an account, no card.
Stuck on your own homework?
Snap it — first scan free, no sign-up
Scanning every week? Scan Standard: for about problems