Ch. 5: Alcohols

Question 1

Alcohols

Answer 1

Have the general form ROH and arenamed with suffix -ol. If they are not the highest priority, they are given prefix hydroxy-. Can hydrogen bond, raising their boiling and melting point relative to corresponding alkanes. Hydrogen bonding also increases the solubility of alcohols

Question 2

Phenols

Answer 2

Benzene rings with hydroxyl groups. Named for the relative positions of the hydroxyl groups: ortho- (adjacent carbons), meta- (separated by one carbon), or para- (on opposite sides of the ring). More acidic than other alcohols bc the aromatic ring can delocalize the charge of the conjugate base.

Question 3

Electron-donating vs Electron withdrawing groups

Answer 3

Electron donating groups like alkyl groups decrease acidity bc they destabilize negative charges. Electron withdrawing groups, such as electronegative atoms and aromatic rings, increase acidity bc they stabilize negative charges

Question 4

Pyridinium chlorochromate (PCC)

Answer 4

Primary alcohols can be oxidized to aldehydes only by PCC; they will be oxidized all the way to carboxylic acids by any stronger oxidizing agents. Secondary alcohols can be oxidized to ketones by any common oxidizing agents

Question 5

Mesylates

Answer 5

Contain the functional group -SO3CH3, which is derived from methanesulfonic acid. Alcohols can be converted to mesylates or tosylates to make them better leaving groups for nucleophilic substitution reactions.

Question 6

Tosylates

Answer 6

Contain the functional group -SO3C6H4CH3, which is derived from toluenesulfonic acid. Alcohols can be converted to mesylates or tosylates to make them better leaving groups for nucleophilic substitution reactions.

Question 7

Aldehydes and Ketones can be protected by converting them

Answer 7

Into acetals or ketals

Question 8

Acetals

Answer 8

Two equivalents of alcohol or dialcohol are reacted with the carbonyl to form an acetal (a primary carbon w 2 -OR groups and hydrogen atom)

Question 9

Ketals

Answer 9

Two equivalents of alcohol or dialcohol are reacted with the carbonyl to form an acetal (a secondary carbon w 2 -OR groups)

Question 10

Deprotection

Answer 10

An acetal or ketal can then be converted back to a carbonyl by catalytic acid in deprotection

Question 11

Quinones

Answer 11

Synthesized through oxidation of phenols. Resonance-stabilized electrophiles. Vitamin K1 (phylloquinone) and Vitamin K2 (the menaquinones) are biochemically relevant quinones

Question 12

Hydroxyquinones

Answer 12

Produced by oxidation of quinones, adding a variable number of hydroxyl groups

Question 13

Ubiquinone (coenzyme Q)

Answer 13

Another biologicaly active quinone that acts as an electron acceptor in Complexes I, II, and III of the electron transport chain. It is reduced to ubiquinol.