Ethers & Epoxide; Thiol & Sulfides

Question 1

Ethers

Answer 1

Are compounds that exhibit an oxygen atom bonded to two R groups

Question 2

What are the two different methods for naming ethers?

Answer 2

1. A common name is constructed by identifying each R group, arranging them in alphabetical order & adding “ether” at the end (ex. ethyl methyl ether)
2. A systematic name is made by choosing the larger group to be the parent alkane & naming the smaller group as an alkoxy substituted (ex. ethoxypentane)

Question 3

An ether can act as a ___________ & interact with the proton of an alcohol (Bu they can’t make hydrogen bonds with themselves) (Boiling point lower than alcohols)

Answer 3

Hydrogen bond acceptor

Question 4

Ethers can have ___________ innteractions

Answer 4

Dipole-Dipole

Question 5

Ethers can interact with ________ that have either a full positive charge or partial positive charge

Answer 5

Metals

Question 6

The formation of a Grignard reagent is formed with an ___________

Answer 6

Ether

Question 7

Polyethers

Answer 7

Compounds that have multiple ether groups & they have stronger interaction with metals

Question 8

Crown ethers are an example of what?

Answer 8

Polyethers

Question 9

____________ contain multiple oxygen atoms & are therefore capable of binding more tightly to metal ions

Answer 9

Crown ethers

Question 10

The nomenclature for crown ether is _____________ where X indicated the total number of atoms in the ring & Y indicates the number of oxygen atoms

Answer 10

X-crown-Y

Question 11

Without ________ the KF wouldn’t dissolve in benzene

Answer 11

18-crown-6

Question 12

The use of _______ allows the creation of free fluoride ions in a nonpolar which makes a substitution reaction possible

Answer 12

18-Crown-6

Question 13

Diethyl ether can be prepared ____________ by an acid- catalyzed dehydration of ethanol (SN2) reaction

Answer 13

Industrially

Question 14

Ether can be prepared via two step process called _____________ ether synthesis

Answer 14

Williamson

Question 15

What is the mechanism for Williamson ether synthesis?

Answer 15

1. Proton transfer
2. Nucleophilic attack

Question 16

Alkoxymercuration-demercuration

Answer 16

Is adding an alcohol RO & H to a double bond to form an ether

Question 17

Acidic cleavage

Answer 17

When heated with concentrated solution of a strong acid, an ether will undergo acidic cleavage in which the ether is converted into two alkyl halides

Question 18

What is the mechanism for acidic cleavage of an ether?

Answer 18

1. Proton transfer
2. SN2

Question 19

When phenyl ether is cleaved under acidic consition the products are ________ & _______

Answer 19

Phenol & an alkyl halide

Question 20

Both _____& _____ are used cleave ether

Answer 20

HBr & HI

Question 21

Ethers undergo autooxidation in the presence of atmosphere oxygen to form ______________

Answer 21

Hydroperoxides

Question 22

Cyclic ethers

Answer 22

Are compounds that contain an oxygen atom in a ring

Question 23

Oxiranes

Answer 23

Are cyclic ethers that contain a 3-membered ring system

Question 24

Epoxide

Answer 24

Are substituted oxiranes that can have up to 4 R groups

Question 25

The simplest epoxide is called what?

Answer 25

Ethylene oxide (common name)

Question 26

What are the two ways to name epoxides?

Answer 26

1. The oxygen atom is considered to be a substituent on the parent chain & the exact location of the epoxide group is identified with two number followed by the term’s “epoxy” (ex. 3-ethyl-2-methyl-2,3-epoxypentane)
2. The parent is considered to be the oxirane ring & any group connected to the ring is a substituent (ex. 2,2-diethyl-3,3-dimethylloxirane)

Question 27

Alkenes can be converted into epoxides when treated with ____________

Answer 27

Peroxy Acid

Question 28

__________ & _____________ acid are the most common peroxy acids

Answer 28

MCPBA & Peroxyacetic

Question 29

The process of coverting an alkene to an epoxide is __________ where if a substituent is cis in the alkene (reactant) then its cis in the epoxide (product) & same with trans

Answer 29

Sterospecific

Question 30

Alkene can be converted into halohydrin with a halogen & water where it can then by converted into an epoxide when treated with a ___________

Answer 30

Strong base (like NaOH)

Question 31

What is the mechanism for an epoxide formation from a halohydrin?

Answer 31

1. Proton transfer
2. Intramolecular SN2

Question 32

An epoxide can be formed from an __________

Answer 32

Alkene (use 1. Br₂, H₂O 2. NaOH) or with MCPBA

Question 33

To get a chiral epoxide would have to use _________ where you can use either (+)-DET or (-)-DET

Answer 33

Chiral catalyst (stereochemical outcome (whether its R or S depends on whether (+) or (-) DET was used)

Question 34

When a epoxide is subjected to attack by a ___________ a ring-opening reaction occurs

Answer 34

Strong nucleophile

Question 35

What is the mechanism for epoxide ring- opening with a strong nucleophile?

Answer 35

1. Nucleophilic attack
2. Proton attack

Question 36

When doing a ring opening epoxide with a strong nucleophile what are the two things have to consider?

Answer 36

1. Regio chemistry
2. Stereochemistry

Question 37

What is the Regio chemistry in a ring opening reaction with a strong nucleophile?

Answer 37

When the starting epoxide is unsymmetrical the nucleophile attack the less substituted position

Question 38

What is the stereochemistry of a ring opening reaction with a strong nucleophile?

Answer 38

When the attack takes place at a chiral center an inversion occurs

Question 39

What is the mechanism for the preparation of sulfides from thiols?

Answer 39

1. Proton transfer
2. SN2

Question 40

Sulfides also undergo oxidation to produce ___________ & ___________

Answer 40

Sulfoxides & Sulfones (1st it produces sulfoxide & it oxidized again produces sulfone)

Question 41

__________ is the oxidizing agent used to convert sulfide into sulfoxide without oxidizing it into a sulfones

Answer 41

NaIO₄ (Sodium meta-periodate)

Question 42

If sulfone is the desired product, then 2 equivalent of___________ is used to convert it into

Answer 42

Hydrogen peroxide