Question

Which is more basic oxygen in an ester?

$R-{\stackrel{O}{\stackrel{||}{C}}}^{\alpha }-\stackrel{\beta }{O}-R$

• A. Carbonyl oxygen, $\alpha$
• B. Carboxyl oxygen, $\beta$
• C. Equally basic
• D. Both are acidic oxygen

Answer 1

The correct option is A Carbonyl oxygen, $\alpha$

$R-{\stackrel{O}{\stackrel{||}{C}}}^{\alpha }-\stackrel{\beta }{O}-R$

$\alpha -O$ oxygen atom can donate lone pair of electron more easily, therefore, it is more basic than $\beta$-oxygen.