1. Chem 1152: Exam 2 Review
Naming Compounds

6. Rules for naming alcohols
For single hydroxy (-OH) group
Step 1: Identify longest chain that includes (-OH) group. Drop –e from hydrocarbon name, and replace with ending –ol.
Step 2: Number this parent chain to give lowest number to carbon with attached (-OH) group.
Step 3: Locate position of (-OH) group.
Step 4: Locate and name all branches attached to parent chain.
Step 5: Include names of all branches (still in alphabetical order) in prefix of compound name. Include location of (-OH) group.
Note: Multiple (-OH) groups are named by addiing diol, triol, etc, to end of alkane without removing -e. 1 2 3 4 2 5 1 4 3
2-ethyl-1-pentanol
2-methyl-1,4-butanediol

7. Naming Alcohols 2,2,4-trimethyl-3-hexanol 5-bromo-3-ethyl-1-pentanol
1,2,4-hexanetriol
3-butyl-2,4-hexanediol
2,2-dimethylcyclopentanol
3-methyl-3-pentanol
1,2-cyclohexanediol
2-isopropyl-1-methylcyclopropanol
3-phenyl-1-propanol

8. Ethers Ether: Oxygen with carbon attached on either side.
Naming ethers
Common Names
Name the two groups attached to the oxygen then add the word ether
If both groups the same, can be named with prefix di-.
IUPAC Names
O-R group is alkoxy.
The –yl ending of smaller R group is replaced by –oxy.
butyl methyl ether
1-methoxybutane
isopropyl propyl ether
1-isopropoxypropane
p-methoxytoluene
ethyl propyl ether
1-ethoxypropane
dipropyl ether
2-methoxy-3,4-dimethylhexane
2-chloro-1-isopropoxypropane
1-propoxypropane

9. 2-methyl-3-hexanethiol
Thiols
Thiols: Sulfur analogs of alcohols (-SH instead of –OH)
Chemically- similar (i.e., form similar compounds)
More volatile (lower BP) than alcohols but less water-soluble
Thiols stink!
This is how skunks defend themselves
Chopped onions emit propanethiol
Thiols found in garlic
Ethanethiol added to natural gas (methane) so you can smell a leak
IUPAC Names for simple thiols
The –SH group is a sulfhydryl group.
Follow the same steps for naming as you do for alcohols, but do not modify alkane ending; instead add –thiol to end of parent.
butanethiol
2-butanethiol
2-methyl-3-hexanethiol

10. Naming Aldehydes pentanal 5-chloropentanal 5-chloro-4-ethylpentanal
2-ethylbutanal
3,4-dimethylhexanal
5-chloro-2-methylbenzaldehyde
m-chloro-benzaldehyde
5-methoxy-2-methylbenzaldehyde

11. 2-fluoro-5-methyl-4-hexanone
Naming Ketones
2-pentanone
5-chloro-2-pentanone
1-chloro-3-pentanone
4-ethylcyclohexanone
2-fluoro-5-methyl-4-hexanone
Ketone: Carbonyl group with two C attached.
Named by replacing –e with –one (IUPAC).
Numbered from end closest to carbonyl group

12. Chem 1152: Exam 2 Review
Reactions

13. Addition reactions to alkenes

14. Addition reactions to alkenes

15. Alcohol Dehydration (Elimination Rxn):
Alcohol Reactions
Alcohol Dehydration (Elimination Rxn):
Alcohol Hydration (Addition Rxn)

16. Alcohol Dehydration to produce alkene
Alcohol Dehydration (Elimination Rxn):
2-butene
1-butene
This rxn (at 180 °C) generates 2 products: 2-butene and 1-butene.
The major product is 2-butene (90%) because both C=C bond carbons are attached to at least one other carbon.
The minor product is 1-butene (10%) because only one of the C=C bond carbons is attached to at least one other carbon.
The major product in these rxns will always be the one resulting in the highest number of carbon groups bonded to the C=C carbons.

17. Alcohol Dehydration to produce ether
Alcohol Dehydration (Elimination Rxn):
alcohol
alcohol
ether
This rxn (at 140 °C) generates an ether and water.
This rxn works mainly with primary alcohols.
Primary (1°)
Hydroxy bearing C is attached to either 0 or 1 other C

18. Alcohol Oxidation for Primary Alcohol
aldehyde
Primary alcohol
Carboxylic acid
Immediate product of oxidation of primary alcohol is aldehyde, which is then readily further oxidized to a carboxylic acid.
The aldehyde product may be isolated before further oxidation by maintaining high temp. and boiling aldehyde out of rxn mixture.
This is possible because aldehydes do not H-bond like alcohols and carboxylic acids.

19. Alcohol Oxidation for Secondary and Tertiary Alcohols
Secondary alcohol
ketone
Product of oxidation of secondary alcohol is a ketone, which resists further oxidation.
Tertiary alcohol

20. Multistep Rxns
The synthesis of most alcohols may require multiple steps (i.e., to get product X from reactant A, a product (B, C …X) must be created).
To solve these problems, work backwards from the final product.
Oxidize 2° alcohol to form ketone.
Use acid-catalyzed hydration (addition) to form alcohol.
The completed series of rxns.

21. Hydrogenation Rxn – Aldehydes
Aldehyde hydrogenation rxn
Alcohol oxidation rxn
Seager SL, Slabaugh MR, Chemistry for Today: General, Organic and Biochemistry, 7th Edition, 2011

22. Hydrogenation Rxns – Ketones
Ketone hydrogenation rxn
Alcohol oxidation rxn
Seager SL, Slabaugh MR, Chemistry for Today: General, Organic and Biochemistry, 7th Edition, 2011

23. Addition of alcohol to aldehydes and ketones
Hemiacetal intermediate
acetal
Hemiketal intermediate
ketal
Hemiacetal is unstable, hard to isolate.
With excess alcohol and an acid catalyst, a stable acetal is formed.
Note the bidirectional arrows

24. Hydrolysis of acetals and ketals
aldehyde
alcohol
ketal
ketone
alcohol
“Cutting by water” is essentially the reverse of the addition of alcohol to either aldehyde or ketone.

25. Intramolecular addition of alcohols to aldehyde
CH2OH 1 6 * H OH H C OH 5 C O 2 H HO C H C C 1 3 4 OH H H C OH 4 C C 3 2 OH H H C OH 5 H OH
CH2 OH 6
Intramolecular hemiacetal
glucose
C1 is hemiacetal carbon.
Attached to it you will find: H, OH, OR and R, just like non-cyclical compounds.

26. Aldehyde Rxns – Testing for Aldehydes
Tollens’ Reagent (reacts with all aldehydes)
Benedict’s Reagent (reacts with some aldehydes)
Benedict’s Reagent reacts with aldehydes that have an alcohol on the adjacent carbon (e.g., glucose)
Products include a red precipitate of copper (I) oxide