Ch 13. Ether (ROR) reactions

Question 1

What are the solvent properties of ethers?

Answer 1

They are polar, aprotic solvents

Question 2

How do you IUPAC name an ether?

Answer 2

use -oxy- in the name
Ex. 2-ethoxypropane

Question 3

How do you name crown ethers?

Answer 3

atoms total + crown + #oxygens

Question 4

How do you get an ether from primary, secondary, tertiary and aromatic alcohols?

Answer 4

Williamson ether synthesis

Question 5

How do you conduct Williamson ether synthesis?

Answer 5

1. NaH
2. Unhindered R-X

Question 6

How can you get an ether from an alkene?

Answer 6

Alkoxymercuration-demercuration

Question 7

What reagents are needed for Alkoxymercuration-demercuration?

Answer 7

1. Hg(OAc)2, ROH
2. NaBH4

Question 8

How do you cleave an ether (break it up?)

Answer 8

By using excess HBr or excess HCl

Question 9

What is an epoxide, and how does it react?

Answer 9

An epoxide is a three membered ring ether, and it is more reactive than other ethers because of it’s heightened ring strain

Question 10

How do you name an epoxide with IUPAC method?

Answer 10

-substituent “epoxy”
- 2 location numbers

ex. 1,2-epoxyethane

Question 11

What are the two routes for epoxide synthesis from an alkene?

Answer 11

1. react with peroxy acid (CO3H)
2. halohydrin route

Question 12

Describe the peroxy acid route that synthesizes an epoxide from an alkene.

Answer 12

Use a peroxy acid.
RCO3H, or mCPBA, where the chlorine helps to react.

Question 13

Describe the halohydrin route of epoxide synthesis.

Answer 13

Start with an alkene, react it with X2 (Cl,Br..) and water, to form a chlorium ion/ bromonium ion (makes chiral center, so enantiomers) and then react it with a base such as pyridine to deprotonate it , which forms the epoxide

Question 14

What does pyridine look like?

Answer 14

It is a base, that is a benzene ring, but a Nitrogen with two lone pairs are at the bottom.

Question 15

What do you get when you react an epoxide with HCl or Water or H3O+?

Answer 15

A 1,2-anti diol.

Question 16

What do you get when you react an epoxide with H+/ in CH3OH (methanol)?

Answer 16

A 1,2-anti ether alcohol

Question 17

What do you get when you react an epoxide with OH- in water?

Answer 17

A 1,2- anti diol

Question 18

What do you get when you react an epoxide with:
1. OR, ROH
2. H3O+

Answer 18

A 1,2 anti diol

Question 19

What do you get when you react an epoxide with
1. R-Li
2. H3O+

Answer 19

A 1,2 anti diol

Question 20

In ACID CONDITIONS, what is true about the regiochemistry of the diols that are created?

Answer 20

The OH group on the MORE substituted C is a DASH, and the OH group on the LESS substituted C is a WEDGE

Question 21

In BASE CONDITIONS, what is true about the regiochemistry of the diols that are created?

Answer 21

The OH group on the MORE substituted C is a WEDGE, and the OH group on the LESS substituted C is a DASH

Question 22

What is another molecule that can open epoxides, that turns it into an alcohol with a RNH group on it?

Answer 22

Amines (Primary and secondary, but not tertiary)

Question 23

What is a Thiolether?

Answer 23

Two R groups with a Sulfur

Question 24

How do you name thiols when it is the PRIORITY group?

Answer 24

-thiol suffix
Ex. propanethiol

Question 25

How do you name thiols when it is the SUBSTITUENT group?

Answer 25

“mercapto”
Ex. 4-mercaptobutan-2-one

Question 26

How do you make a thiol (RSH)?

Answer 26

By reacting an alkyl halide (RX) with an SH-

Question 27

How do you make a Thioether from a Thiol?

Answer 27

By reacting the thiol with
1. NaOH or any other base
2. an unhindered alkyl halide