Chemical Forums

Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: foxthreefour on June 13, 2018, 06:26:31 AM

Title: Dual imiscible solvent reaction speed
Post by: foxthreefour on June 13, 2018, 06:26:31 AM
This may be common sense but I can’t seem to find any articles or reference material to explain whether dual solvents that are immiscible, containing a single compound dissolved in each would provide a slower reaction than if they were miscible solvents. Example say, NH3 in MeOH rather than in H2O reacting with a compound dissolved in DCM.
Title: Re: Dual imiscible solvent reaction speed
Post by: clarkstill on June 13, 2018, 08:07:34 AM
They definitely do react more slowly if the two reagents are in immiscible phases. In fact, an entire field of catalysis is dedicated to increasing the rate of such reactions - "phase-transfer catalysis".
Title: Re: Dual imiscible solvent reaction speed
Post by: foxthreefour on June 13, 2018, 08:01:00 PM
They definitely do react more slowly if the two reagents are in immiscible phases. In fact, an entire field of catalysis is dedicated to increasing the rate of such reactions - "phase-transfer catalysis".

Thank you, very informative.
Title: Re: Dual imiscible solvent reaction speed
Post by: hypervalent_iodine on June 14, 2018, 12:46:50 AM
You can think about it very simply in terms of collision frequency. For molecules to react, they must hit one another with enough energy and in the correct orientation. If you have everything dissolved in one solution, you are likely to get more collision (and thus a faster reaction) than if one reactant were separated from the other into two different phases, since collisions could really only occur at the interface between the phases.