In "March's Advanced Organic Chemistry" I have read about the general mechanism of the acetal hydrolysis. It names the acid-catalyzed SN1 or SN2 as a possible mechanism for a Acetal-hydrolysis.
Now I am interested to know if SN1 or SN2 is mainly going on at the Hydrolysis of Sucrose to Glucose and Fructose. So I compared the different parameters which influence SN1/SN2.
Polarity of the solvent: Water -> really polar -> SN1 preferred.
Stabilization of a possible Carbokation-Intermediat: Primary (Anomeric C!), so not really stabilized by Hyperconjunction -> SN2 preferred. (Is there Hyperconjunction also in the ether-O?)
Mesomeric stabilization There is also a mesomeric stabilization between the resulting carbocation and a Oxonium-Ion in the SN1-Mechanism.
Steric Hindrance: In my opinion, through the planar region around the anomeric C (planar ether), there is no steric hindrance -> SN2 possible.
Temperature: high temperature -> SN1 preferred.
So to conclude: Many different aspects. Because of the main points "steric hindrance" and the destabilized primary carbocation intermediate I would conclude that the hydrolysis of Sucrose goes mainly (maybe a little bit over SN1) over SN2.
Have I forgotten something important? Are my assumptions "No steric hindrance" and primary carbocation-intermediate correct?
I have attached my possible SN1-mechanism.