The Sn2 Mechanism: Synthesis of Butyl Naphthyl Ether

Question 1

why did naphthol undergo the Sn2 instead of the Sn1 mechanism?

Answer 1

it is a secondary alcohol that had basic reaction conditions

Question 2

what is the leaving group in this reaction?

Answer 2

hydrogen (H)

Question 3

what is the nucleophile?

Answer 3

the 2-naphthoxide ion

Question 4

what is the electrophile?

Answer 4

iodobutane

Question 5

what is the rate determining step

Answer 5

the bimolecular dissociation of iodine from 1-iodobutance and the association of the naphthoxide ion wit the electrophilic butyl group

Question 6

what is the purpose of ethanol in the reaction

Answer 6

to dissolve the sodium hydroxide flakes without deprotonating the sodium hydroxide

Question 7

what is the purpose of sodium hydroxide in the reaction?

Answer 7

to deprotonate the hydroxyl group on the naphthyl compound, to yield the 2-naphthoxide ion

Question 8

what is the purpose of iodobutane?

Answer 8

act as an electrophile and attack the 2-naphthoxide ion to form butyl naphthyl ether

Question 9

What are the safety hazards of this experiment?

Answer 9

• sodium hydroxide is corrosive to the skin and eyes; wear goggle and long sleeved lab coat
• ethanol and 1-iodobutane are volatile and fumes are toxic; use fume hood

Question 10

why must the contents be stirred with a magnetic stir bar?

Answer 10

to avoid bumping

Question 11

what is the purpose of refluxing the reaction?

Answer 11

refluxing allows the solution to be heated for a long amount of time without losing product in evaporation

Question 12

why is it important to add iodobutane dropwise into the round bottom flask?

Answer 12

to allow proper incorporation of the compound without shocking the reaction

Question 13

what is the purpose of pouring the liquid over ice?

Answer 13

• it cools the solution and allows the product to precipitate

Question 14

what is the ideal melting point of the solid?

Answer 14

33-35*C

Question 15

What are the steps to this reaction?

Answer 15

1. add magnetic stir bar, ethanol, sodium hydroxide flakes, and 2-naphthol to a round bottom flask
2. set up on stirring plate and heating mantle
   3.attach jacketed distillation column to rbf with glass stopper. Fit column with correct water tubing
3. turn on stirring high
4. heat solution to reflux until NaOH and 2-naphthol have dissolved. Allow solution to cool for 5 min
5. slowly add in 1-iodobutane
6. reflux for 1.5 hr and then allow soln to cool
7. pour liquid over ice and allow ice to melt completely
8. vacuum filtrate the liquid. allow product to dry. mass. test melting point

Question 16

what is the first step of the Sn2 reaction?

Answer 16

dissociation of halide from alkyl chain