4.11 Ethers

Reminder: what are ethers?

Ethers are hydrocarbons possessing a C-O-C functional group that links two organic molecules together.

• This C-O-C functional group is known as an alkoxyl.

How are ethers created

Recall the dehydration reaction of alcohols. When an alcohol is dehydrated, it forms an alkene and water. However, depending on the temperature of the reaction, it can also form ethers.

• Ethers (140 degrees celsius)

• Alkene (180 degrees celsius)

How to name ethers

Step 1: change “-yl” ending of side group name to “oxy”

• methyl → methoxy (if the side group is the oxygen bridging a single alkyl to the parent chain)

Step 2: Assign carbon number factoring that alkoxyls have greater priority than alkyls and halides but lesser than multiple bonds, carbonyls, and alcohols.

Step 3: If the side group including the oxygen has individual functional groups within it, write the location of the entire functional group followed by bracket, the individual locations of the functional groups.

• Thats pretty confusing to explain verbally so look at notes.

What is the polarity of an alkoxyl

C-O bonds are less polar than O-H bonds but are still slightly polar, allowing them to also be soluble in water

What is the B point of an ether compared to an alcohol of equal carbon number

Ethers cannot form hydrogen bonds between themselves and thus will have lower B points than alcohols of same carbon number.

What is the reactivity of an ether

Ethers have low reactivity yet are highly flammable.

Why are ethers excellent extracting agents for organic compounds?

Ethers are excellent extracting agents for organic compounds because organic compounds are more soluble in ethers than water.