Usually, the addition of alcohol to an alkene needs to be catalysed by Bronsted acid. However, I am using heterogenous Zirconia-silica catalyst with the zirconia present in the silica tetrahedral framework. Hence, it is not expected to have much Bronsted acidity. However, I managed to get the ether product using such catalyst. As such, I am asking for help with the organic mechanism. Thanks greatly
Hi Candy,
Since, you mentioned that you managed to get the ether product using the said catalyst, what I can suggest is that there are two sites in this catalyst. One site is Bronsted acid site and other is Lewis acid site. It is difficult to say which site is actively or completely involved in the mechanism. You can have a look on attached references. They might give you some hint.
Thanks
With alcohol being nearly neutral pH, and the alkene being potentially unstable almost any metal, acid, or base can catalyze the addition at some temperature, conversion, and purity level.
The case of isobutylene is particularly interesting yielding either t- butyl or iso-butyl ether depending on the choice of catalyst and operating conditions.
In your question it would be helpful to determine which isomer of your ether you are getting or ratio of isomers, as a clue to the mechanism.
The addition of alcohol to an alkene to form ether be catalysed by an Lewis acid catalyst .It is possible because alcohol in presence of Lewis acid releases proton which protonates an alkene to form carbocation which gets attacked by alcohol to form oxonium iob which releases proton to form an ether.