Consider the following functional and isotopic substituent groups: , , , , , , . How many of these s — GOC and Organic Chemistry Basics Chemistry Question
Question
Consider the following functional and isotopic substituent groups: $-CH_3$, $-C_2H_5$, $-NO_2$, $-OH$, $-OCH_3$, $-CF_3$, $-COO^-$. How many of these specified groups predominantly exert a positive inductive ($+I$) effect, which fundamentally decreases the acidic strength of a molecule when attached to the carbon chain?
💡 Solution & Explanation
The groups that act as electron donors via the $\sigma$ -bond framework ($+I$ effect) are standard alkyl groups ($-CH_3$, $-C_2H_5$) and negatively charged ions which strongly repel electron density ($-COO^-$). Groups like $-NO_2$, $-OH$, $-OCH_3$, and $-CF_3$ feature electronegative atoms directly bonded to the chain and exert a negative inductive ($-I$) effect. Total $+I$ groups = 3.