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What are alcohols? An alcohol contains a hydroxyl group (—OH) attached to a carbon chain. A phenol contains a hydroxyl group (—OH) attached to a benzene.

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Presentation on theme: "What are alcohols? An alcohol contains a hydroxyl group (—OH) attached to a carbon chain. A phenol contains a hydroxyl group (—OH) attached to a benzene."— Presentation transcript:

1 What are alcohols? An alcohol contains a hydroxyl group (—OH) attached to a carbon chain. A phenol contains a hydroxyl group (—OH) attached to a benzene ring. 1 alcohol water phenol

2 How do we name alcohols? Formula IUPACName CH 4 methane CH 3 ─ OH methanol CH 3 ─ CH 3 ethane CH 3 ─ CH 2 ─ OH ethanol The names of alcohols in IUPAC replace the -e with -ol.

3 More names of alcohols CH 3 ─ CH 2 ─ CH 2 ─ OH 1-propanol OH │ CH 3 ─ CH ─ CH 2 ─ CH 3 2-butanol CH 3 OH │ CH 3 ─ CH ─ CH 2 ─ CH 2 ─ CH ─ CH 3 5-methyl-2-hexanol 6 5 4 3 2 1 IUPAC names for longer chains number chain from –end nearest -OH group. 3

4 What are phenols? Phenol IUPAC name for benzene with a hydroxyl group. is used in antiseptics and disinfectants. 4 phenol resorcinol 4-hexylresorcinol

5 Derivatives of Phenol Compounds of phenol are the active ingredients in the essential oils of cloves, vanilla, nutmeg, and mint. 5

6 How to name a phenol! 6 3-chlorophenol 4-bromophenol 3 4 1 1 To name a phenol with two substituents, assign C-1 to carbon attached to –OH. Number ring to give lowest numbers.

7 7 determined by number of alkyl groups attached to carbon bonded to hydroxyl. primary (1°), secondary (2°), or tertiary(3). Primary (1º) Secondary (2º) Tertiary (3º) 1 group 2 groups 3 groups H CH 3 CH 3 | | | CH 3 —C—OH CH 3 —C—OH CH 3 —C—OH | | | H H CH 3 Classification of alcohols

8 8 What are ethers? An ether contains an ─ O ─ between two carbon groups. has a common name that gives alkyl names of attached groups followed by ether. CH 3 ─ O ─ CH 3 CH 3 ─ CH 2 ─ O ─ CH 3 dimethyl ether ethyl methyl ether

9 9 Ethers as anesthetics Anesthetics inhibit pain signals to the brain. like diethyl ether CH 3 ─ CH 2 ─ O ─ CH 2 ─ CH 3 were used for over a century, but caused nausea and were flammable. developed by the 1960’s were nonflammable. Cl F F Cl F H │ │ │ │ │ │ H ─ C ─ C ─ O ─ C ─ HH ─ C ─ C ─ O ─ C ─ H │ │ │ │ │ │ F F F H F H Ethane(enflurane) Penthrane

10 10 Now let’s look at the Properties of Alcohols and Ethers, Alcohols contain polar OH groups. form hydrogen bonds with other alcohol molecules. have higher boiling points than alkanes and ethers of similar mass.

11 11 However ethers………… Ethers do not have a polar group. have an O atom, but there is no H attached. cannot form hydrogen bonds between ether molecules.

12 12 Solubility of alcohols and ethers in water Alcohols and ethers are more soluble in water than alkanes because the oxygen atom can hydrogen bond with water. with 1-4 C atoms are soluble, but not with 5 or more C atoms.

13 13 Reactions of alcohols are… Alcohols undergo combustion with O 2 to produce CO 2 and H 2 O. 2CH 3 OH + 3O 2 2CO 2 + 4H 2 O + Heat

14 14 Alcohols undergo dehydration when heated with an acid catalyst. the loss of —H and —OH from adjacent carbon atoms. H OH | | H +, heat H—C—C—H H—C=C—H + H 2 O | | H H H H alcohol alkene Dehydration of Alcohols

15 15 Oxidation vs Reduction In an oxidation, there is an increase in the number of C-O bonds. there is a loss of H. In a reduction, there is an decrease in the number of C-O bonds. there is a gain of H.

16 16 When a primary alcohol is oxidized, [O], one H is removed from the –OH. another H is removed from the carbon bonded to the OH. an aldehyde is produced. [O] Primary alcohol Aldehyde OH O | [O] || CH 3 —C—H CH 3 —C—H + H 2 O | H Ethanol Ethanal (ethyl alcohol) (acetaldehyde) Oxidation of primary (1  ) alcohols

17 17 Oxidation of secondary (2  ) alcohols When a secondary alcohol is oxidized, [O], one H is removed from the –OH. another H is removed from the carbon bonded to the OH. a ketone is produced. secondary alcohol [O] ketone OH O │ ║ CH 3 ─ C ─ CH 3 [O] CH 3 ─ C ─ CH 3 + H 2 O │ H 2-propanol 2-propanone

18 18 Oxidation of tertiary ( 3)  alcohols Tertiary 3  alcohols do not readily oxidize. [O] Tertiary alcoholno reaction OH │ [O] CH 3 ─ C ─ CH 3 no product │ CH 3 no H on the C-OH to oxidize 2-methyl-2-propanol

19 19 Oxidation of Ethanol in the Body In the body, enzymes in the liver oxidize ethanol. aldehyde product impairs coordination. blood alcohol over 0.4% can be fatal. O O ║ CH 3 CH 2 OH CH 3 CH CH 3 COH 2CO 2 + H 2 O ethyl alcohol acetaldehyde acetic acid

20 20 Ethanol acts as a depressant. kills or disables more people than any other drug. is metabolized at a rate of 12-15 mg/dL per hour by a social drinker. is metabolized at a rate of 30 mg/dL per hour by an alcoholic. Ethanol CH 3 CH 2 OH % EthanolProduct 50% Whiskey, rum, brandy 40% Flavoring extracts 15-25% Listerine, Nyquil, Scope 12% Wine, Dristan, Cepacol 3-9% Beer, Lavoris

21 21 What do Aldehydes and Ketones have in common? A carbonyl group in an aldehyde is attached to at least one H atom. in a ketone is attached to two carbon groups.

22 22 More examples! Benzaldehyde (almonds)

23 23 How to name ketones In naming ketones as IUPAC, -e in alkane name replaced with –one. With a common name, alkyl groups attached to carbonyl group are named alphabetically followed by ketone. O O ║ CH 3 ─ C ─ CH 3 CH 3 ─ C ─ CH 2 ─ CH 3 propanone 2-butanone

24 24 Are they soluble? aldehydes and ketones electronegative O atom of carbonyl group aldehydes and ketones hydrogen bonds with water not between each other, thus higher boiling points alkanes and ethers of similar mass. lower boiling points alcohols of similar mass.

25 25 Reactions of aldehydes Aldehydes oxidize readily to carboxylic acids. Ketones do not oxidize further O O || || CH 3 —C—H  CH 3 —C—OH oxidation O || CH 3 —C— CH 3-------  NO REACTION oxidation


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