Natural rubber is attacked readily by ozone. If the resulting material is treated with \(\mathrm{H}_{2} \mathrm{O}_{2}\) in acetic acid, the major product isolated is levulinic acid \(\left(\mathrm{C}_{5} \mathrm{H}_{8} \mathrm{O}_{3}\right)\). (a) What is the structure of levulinic acid? (b) If a rubber plant is fed radioactive sodium acetate labeled only at the acetate methyl \(\left({ }^{*} \mathrm{CH}_{3} \mathrm{CO}^{-}{ }_{2} \mathrm{Na}^{+}\right)\), radioactive rubber can be obtained from the latex of the plant after a short time. Degradation of this rubber by ozone yields radioactive levulinic acid. Which specific carbon atoms of the levulinic acid would you expect to be radioactive?

Step by step solution

01

Structure of Levulinic Acid

Levulinic acid has the molecular formula C5H8O3. To find the structure, we draw a five-carbon chain, then add oxygen atoms to form a carboxyl group on one end and a ketone group in the middle. The structure of levulinic acid is: \[ \mathrm{CH_3CH_2C(O)CH_2COOH} \]

02

Radioactive Sodium Acetate and Rubber Plant

The exercise states that the rubber plant is fed with radioactive sodium acetate, labeled only at the acetate methyl group. The formula for this compound is: \[ ^{*}\mathrm{CH_3CO^{-}_{2}Na^{+}} \]

03

Formation and Degradation of Rubber

After the plant is fed with radioactive sodium acetate, radioactive rubber is obtained from the latex. When this rubber is degraded by ozone, the resulting product is radioactive levulinic acid. We need to identify which specific carbon atoms in levulinic acid would be radioactive.

04

Identify Radioactive Carbon Atoms

To determine which specific carbon atoms in levulinic acid are radioactive, we must consider that the radioactive label came from the radioactive sodium acetate. After the treatment with ozone and hydrogen peroxide in acetic acid, the radioactive label will appear in the structure of levulinic acid. The carbon atoms in the acetate methyl group are: \[ ^{*}\mathrm{CH_3} \] Based on this, the radioactive carbon atoms in levulinic acid would be the C1 (methyl) carbon, as it is originally part of the labeled methyl group from radioactive sodium acetate: \[ ^{*}\mathrm{CH_3CH_2C(O)CH_2COOH} \] So, the specific carbon atoms in levulinic acid that would be radioactive are the C1 (methyl) carbon atoms.

Unlock Step-by-Step Solutions & Ace Your Exams!

• Full Textbook Solutions

  Get detailed explanations and key concepts

• Unlimited Al creation

  Al flashcards, explanations, exams and more...

• Ads-free access

  To over 500 millions flashcards

• Money-back guarantee

  We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!