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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: G O D I V A on November 13, 2009, 05:58:18 AM

Title: Reaction rates question
Post by: G O D I V A on November 13, 2009, 05:58:18 AM

Consider:

(1) (CH₃)₃CBr + CH₃OH (in methanol)

and

(2) (Ph)CBr(CH3)₂ + CH₃OH (in methanol, solvent) -- (Thats 2-bromo-2-phenylbutane)

At 25 celcius and after 1 hour, which reaction will produce more of the substitution product?


I'm not understanding that.  Is the "substitution product" the product; i.e. (1) would be H₂C=C(CH₃)₂ and (2) would be 2-phenyl-2-butanol?

How would I determine which would be faster?

Title: Re: Reaction rates question
Post by: Dan on November 14, 2009, 05:08:52 AM

Quote from: G O D I V A on November 13, 2009, 05:58:18 AM

I'm not understanding that.  Is the "substitution product" the product; i.e. (1) would be H₂C=C(CH₃)₂ and (2) would be 2-phenyl-2-butanol?

No, neither of those are the correct products.

For (1), you have given an elimination product, and for (2) you have assumed the presence of water, which is not given in the question.

Look up nucleophilic substitution in your textbook, or google it, and decide which mechanism is operating in each case (S_N1 or S_N2).

Once you work out which mechanism is operating, you can work out the products and which reaction is faster.