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Alcohols and Ethers. Alcohols. Organic compounds containing a hydroxyl group -OH E.g. ethanol, cholesterol, retinol (vitamin A) Naming: -ol suffix e.g. methane + OH = methanol. Polyalcohols. Alcohols containing more than one -OH group -diol, -triol suffix Or hydroxy prefix.
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Alcohols • Organic compounds containing a hydroxyl group -OH • E.g. ethanol, cholesterol, retinol (vitamin A) Naming: • -ol suffix e.g. methane + OH = methanol
Polyalcohols • Alcohols containing more than one -OH group • -diol, -triol suffix • Or hydroxy prefix 1,2-dihydroxyethane 1,2,3-trihydroxypropane
Primary, Secondary, Tertiary Alcohols • Depends on the number of carbon groups the hydroxyl containing carbon is attached to • 1 other carbon atom- primary • 2 other carbon atoms –secondary • 3 carbon atoms –tertiary
Properties of Alcohols • More polar and can hydrogen bond • Higher boiling points • More soluble in polar solvents • Long-chain alcohols are nonpolar (hydrocarbon portion) and polar (-OH) • Ideal solvents in organic reactions because they will dissolve both polar and nonpolar compounds
Preparing Alcohols:Hydration Reactions • Alkene + water --> alcohol • Follows Markovnikov’s rule Combustion of Alcohols
Elimination Reactions Dehydration (Condensation) Reactions: • Under certain conditions alcohols can decompose to produce alkenes and water • A catalyst (sulfuric acid) removes a hydrogen atom and a hydroxyl group from neighbouring carbons • Resulting in C=C and H2O
Ethers • Molecules with C-O-C group • More polar than hydrocarbons • But, unlike alcohols, ethers cannot hydrogen bond • Naming: • Add oxy to the prefix of the smaller hydrocarbon group and join it to the alkane name of the larger hydrocarbon group • E.g. CH3-O-C2H5 is methoxyethane
Condensation Reactions • When two alcohols combine, an ether and water are formed