How can phenol be converted to aspirin?

(N/A) Phenol is converted to aspirin through the following steps:
$1$. Kolbe reaction: Phenol is treated with $NaOH$ followed by $CO_2$ at $4-7 \ atm$ pressure and $393 \ K$ to form salicylic acid ($2$-hydroxybenzoic acid).
$2$. Acetylation: Salicylic acid is treated with acetic anhydride in the presence of an acid catalyst to form aspirin (acetylsalicylic acid).