Question

Calculate the $\log P$ value for the structure shown; $\log P$ for benzene = 2.13; $\pi$(OH) = -0.67; $\pi$(CH$_3$) = 0.52

• A. 3.32
• B. 0.94
• C. 1.98
• D. 2.13

Answer 1

The Correct Option is C

Step 1: Understanding the Partition Coefficient ($\log P$) The partition coefficient ($\log P$) represents the lipophilicity of a molecule, which is calculated using additive fragment values.

Step 2: Applying the Given Values The given structure is p-cresol (4-methylphenol), and its $\log P$ value is calculated using the formula: \[ \log P = \log P_{\text{benzene}} + \pi(\text{CH}_3) + \pi(\text{OH}) \] Substituting the given values: \[ \log P = 2.13 + 0.52 - 0.67 \]

Step 3: Calculation \[ \log P = 2.13 + 0.52 - 0.67 = 1.98 \]

Step 4: Selecting the Correct Answer Thus, the correct answer is 1.98 (Option C).