Description:
Esters are a group of compounds in organic chemistry, characterized by their distinct functional group seen above. Esters typically have a low boiling point (compared to carboxylic acids), due their lack of hydrogen bonding--no hydrogen bonding occurs because both oxygen atoms have formed two bonds, leaving them unavailable for hydrogen bonding with other ester molecules. However, they do form hydrogen bonds with water molecules, which makes them more soluble. One notable property of esters is their sweet smell. Many esters smell fruity or sweet.
Reaction:
Esters can actually be created from alcohol and acid in esterification. Aka Fischer Esterification, one molecule of alcohol is combined with a molecule of an organic acid to produce an ester and a water molecule. The reaction mechanism can be seen below.
Esters are a group of compounds in organic chemistry, characterized by their distinct functional group seen above. Esters typically have a low boiling point (compared to carboxylic acids), due their lack of hydrogen bonding--no hydrogen bonding occurs because both oxygen atoms have formed two bonds, leaving them unavailable for hydrogen bonding with other ester molecules. However, they do form hydrogen bonds with water molecules, which makes them more soluble. One notable property of esters is their sweet smell. Many esters smell fruity or sweet.
Reaction:
Esters can actually be created from alcohol and acid in esterification. Aka Fischer Esterification, one molecule of alcohol is combined with a molecule of an organic acid to produce an ester and a water molecule. The reaction mechanism can be seen below.
Applications:
Actually, its esters that give flowers their sweet smell and fruits their sweet odors. Because of the ester's sweet smell, esters are often used in perfumes to enhance their fragrances. For instance, isopentyl acetate can be used as a fragrance, and it is also present in bananas, giving them their sweet smells.
Esters are also used as flavoring agents in food. For instance, each of the following esters are associated with a flavor:
Ethyl acetate--wine
Ethyl formate--rum
N-amyl acetate--pears and bananas
N-octyl acetate--oranges
Methyl butrate--apples
Ethyl butyrate--similar to pineapple
Anisyl propionate--sweet, fruity, floral, vanilla
2-phenethyl acetate--apricot, peach vanilla, tutti-frutti
2-phenethyl hexanoate--pineapple, rose, apple, banana, fruity
1-phenethyl acetate--rose, honey, fruity, floral
Actually, its esters that give flowers their sweet smell and fruits their sweet odors. Because of the ester's sweet smell, esters are often used in perfumes to enhance their fragrances. For instance, isopentyl acetate can be used as a fragrance, and it is also present in bananas, giving them their sweet smells.
Esters are also used as flavoring agents in food. For instance, each of the following esters are associated with a flavor:
Ethyl acetate--wine
Ethyl formate--rum
N-amyl acetate--pears and bananas
N-octyl acetate--oranges
Methyl butrate--apples
Ethyl butyrate--similar to pineapple
Anisyl propionate--sweet, fruity, floral, vanilla
2-phenethyl acetate--apricot, peach vanilla, tutti-frutti
2-phenethyl hexanoate--pineapple, rose, apple, banana, fruity
1-phenethyl acetate--rose, honey, fruity, floral
