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Which reaction proceeds faster?

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Please help with the following problem.

For an SN2 reaction, the effect of solvent polarity is usually much less, but the ability (or really lack there of) of the solvent to solvate the nucleophile is the important criteria.

Which of the two reactions proceed faster:

a.) CH3CH2I in presence of ethanol

or

b.) CH3CH2I in presence of dimethyl sulfoxide

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https://brainmass.com/chemistry/organic-reaction-intermediates-and-mechanisms/which-reaction-proceeds-faster-118536

Solution Preview

The reaction is a SN2 reaction.

For an SN2 reaction, the effect of solvent polarity is usually much less, but the ability (or really lack there of) of the solvent to solvate the nucleophile is the important criteria.

The solvent used in a substitution reaction will influence which pathway will be chosen. There are three major categories of solvent.

Polar Protic Solvents
Polar Aprotic Solvents
Non-Polar Aprotic ...

Solution Summary

The following posting helps with a problem involving organic reaction intermediates and mechanisms. The concepts covered in the solution include SN2 reactions, solvent polarity and nucleophiles. Detailed explanations are given.

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