Answer to Question #111004 in Organic Chemistry for kylie

Question

What is the best way to prepare CH3OCH(CH3)2 by an SN2 reaction?

(1) (CH3)2CHI and CH3ONa
(2) CH3OH and (CH3)2CHI
(3) CH3Br and (CH3)2CHOH
(4) CH3I and NaOCH(CH3)2

Answer 1

Solution:

The Williamson Ether Synthesis is an S_N2 reaction between a deprotonated alcohol [“alkoxide”] and an alkyl halide that forms an ether.

Methyl and primary alkyl halides are excellent substrates for the Williamson Ether reaction.

The reaction of RO^– with an alkyl halide is always going to be much faster than the reaction of ROH because of the higher electron density on the nucleophile (oxygen). That’s why RO^– is used.

Therefore,

The best way to prepare CH₃OCH(CH₃)₂ by an SN₂ reaction is (4) CH₃I and NaOCH(CH₃)₂.

Answer: (4) CH₃I + NaOCH(CH₃)₂