Question

Choose the correct statement(s) with regard to the terpenes given below.

• A. Upon ozonolysis, all the terpenes would produce at least one identical carbonyl compound
• B. Terpenes N and O are geometrical isomers
• C. Terpene O cannot undergo Diels-Alder reaction with maleic anhydride
• D. Amongst all, $\lambda_{\max}$ for $\pi-\pi^*$ absorption is the lowest for terpene P

Hint:

Greater conjugation increases $\lambda_{\max}$For Diels-Alder reaction, look for a conjugated diene capable of adopting s-cis conformation

Answer 1

The Correct Option is A, B, D

Step 1: Common fragment.
All the terpenes share one alkene fragment, so ozonolysis gives at least one common carbonyl product. Statement A is correct.

Step 2: N and O.
N and O differ only in the arrangement about one double bond, so they are geometrical isomers. Statement B is correct.

Step 3: Wavelength.
Terpene P has the least conjugation, so it absorbs at the lowest wavelength. Statement D is correct, while the Diels-Alder claim in C is wrong.

Step 4: Answer.
\[ \boxed{\text{A, B and D}} \]