Alcohols, Phenols, and Ethers in Chemistry

Phenol

Compound in which an —OH group is connected to a benzene ring

Diols

Alcohols containing two —OH groups

Triols

Alcohols containing three —OH groups

Solubility of Alcohols with three carbon atoms or fewer

Infinitely soluble in water

Solubility of Alcohols with four or more carbon atoms

Have limited solubility in water

Effect of added -OH groups on solubility

Increase the solubility

D-glucose

Solubility = 95g/100g H2O

Hydrogen bonds in alcohols

The —OH group can make hydrogen bonds between alcohol molecules that lead to relatively high boiling points.

Dehydration Reaction

Reaction in which water is chemically removed from a compound.

Dehydration Reaction temperature

At 140°C, the main product is an ether.

Elimination reaction

Two or more covalent bonds are broken and a new multiple bond is formed.

Alcohol oxidation agents

Reactions with oxidizing agents such as K2Cr2O7 and KMnO4.

Primary alcohol

Oxidizes to aldehyde and then to carboxylic acid.

Secondary alcohol

Oxidizes to ketone.

Phenol

C6H5OH; a weak acid with a melting point of 41°C.

Phenols

Compounds that can react with bases to form salt and are used as disinfectants and antioxidants.

Naming Ethers - IUPAC

The method of naming ethers by naming the smaller R group as an alkoxy group and replacing the -yl ending with -oxy.

Cyclic Ethers

Ethers that are part of a heterocyclic ring, which includes atoms other than carbon.

Properties of Ethers

Ethers are much less polar than alcohols, more soluble in water than hydrocarbons, have low boiling and melting points, are inert, and highly flammable.

Thiol

A compound containing an —SH group, characterized by a strong and offensive odor.

Thiol Reactions - Oxidation

The process that forms disulfide (—S—S—) linkages, important structural features of some proteins.

Thiol Reactions - Reducing Agent

Oxidation reactions of thiols can be reversed with a reducing agent such as H2.

Thiol Reactions - Heavy Metal Ions

Thiols react with heavy metal ions (Pb2+, Hg2+) to form insoluble compounds that can have adverse biological effects.

Polyfunctional Compound

A compound with two or more functional groups that determine its chemical properties.