The +I Effect & Bond Breakage in Alcohols & Acids

[opencircuit]

In alcohols, the negative charge on 'Oxygen atom' increases due to '+I effect' of alkyl groups. While in acids, the '+I effect' of alkyl groups decreases the positive charge on the 'Carbon atom'.

In the first case the +I effect makes it easier to break the C-O bond while in the second case the +I effect makes the breakage of 'C=O' bond difficult. Please explain.

 

[morrobay]

In terms of the second case with the carboxyl group: The + charge about the carbon
promotes an electron withdrawing effect on the hydroxyl oxygen by induction. This facilitates release of the proton.
The carboxylate anion is then stablized as a two structure resonance hybrid.

=O
C
-O^-


-O^-
C
=O

note: scroll down to the Chemistry section as this type of question is better there