Chap 7: Alcohols, Phenols, & Thiols
Objectives: Chap 7: Alcohols, Phenols, & Thiols (Chapter 7 and pages 283-285 & 296-297, A-1 & A-2 in lab manual)
- Identify molecules as an alcohol, phenol, glycol, glycerol, quinone, aldehyde, ketone, carboxylic acid, ether, ester, thiol, and thiophenol
- Uses, dangers, common names/nicknames, biological significance from notes, reading assignments, class discussions
- Determine the IUPAC name of alcohols, phenols, thiols, thiophenols, carboxylic acids, esters, or their structures.
- Classify alcohols as 1o, 2o, 3o
- Explain the properties of acidity & boiling point as relates to alcohols & phenols.
- Rank given molecules according to acidity
- Define and identify acids and bases according to the Arrhenius, Bronsted-Lowry and Lewis models
- Identify conjugate acid-base pairs, acid ionization equations, acid strength using Ka and pKa
- Determine equations, reactants, catalysts, products and predominant products for the following reactions of alcohols & phenols.
- Dehydration
- Halogenation; (PX3 vs. HX for alcohols) (X2 w/FeX3 for phenols)
- Oxidation; Jones (CrO3, Acetone, H2SO4) vs. PCC
- Nitration
- Oxidation of Thiols
- Ester formation
- Miscellaneous phenol reactions – see Reaction Summary Sheet or Chapter 4
Alcohol: ______
Phenol: ______
Thiol: ______
Thiophenol: ______
Alcohol Names
IUPAC name:
- Hydroxyl group ______
- Use longest chain w/-OH
- Number beginning nearest the -OH
- Common name: Alkyl group name followed by “alcohol”
- Examples:
- Unsaturated alcohols: 2 endings
- ene or yne for double/triple bond
- ol for the hydroxyl group. (Listed last & given numbering priority)
- Example:
Phenol Names:
- Phenol: Parent name
- Hydroxy: To name -OH as substituent group when benzene ring has larger substituent w/common name
Thiols & thiophenol Names:
- Thiols: Named like alcohols except ______
- Thiophenol: common name of benzene ring ______
- Mercapto: ______
Formula
Old common name / Uses / Dangers
Methanol (methyl alcohol)
Ethanol (ethyl alcohol):
2-propanol:
Classification of Alcohols
- Based on ______
- Methanol considered _____
Hydrogen Bonding in Alcohols & Phenols
- Hydrogen bonds form ______
- ______than alkanes of similar molecular mass
- Low mass alcohols ______
- May be ______in nonpolar solvents ______
Acids & Bases
Arrhenius Model
- Acid: Substance that ______
- Base: Substance that ______
- Shortcomings:
- ______
- ______
Bronsted-Lowry Model
- May not CONTAIN H+ or OH-, just ______
- Acid: ______
- Base: ______
- Conjugate acid-base pair: ______
______
- Example:
HClO2 + H2O H3O+ + ClO2-1
- Acid: Left side that ______
- Conjugate Base: Other side of equation ______
- Conjugate pair: ______
- Base: Left side that ______
- Conjugate Acid: Right side ______
- Conjugate Pair: ______
- Amphoteric: Substances that can act ______. Example ______
- Example of water as an acid:
NH3 + H2O
Lewis Acids & Bases ______
- Lewis Acid: Substance that ______when forming a bond
- ______
- Has an ______OR ______
- Lewis Base: Substance that ______to form a bond
- ______
- ______
Acid vs. Base Determination? The following questions may be helpful;
- Was H+ transferred? If so, it probably follows the ______
- Is the valence complete (especially in the center atom)? No- it might be a ______
- Is there a + charge that could be neutralized by accepting an e- pair? If so, it might be a ______
- If the valence is ok, are there any unshared electron pairs that can be donated and used to make a bond? If so, it might be a ______.
Acid / Base
Bronsted-Lowry
Lewis
Acid ionization constants
- Ionization equation for hydrocyanic acid, HCN
- Acid ionization constant, K a
- Indicates the ______
- ______number is ______
- Examples of typical numbers:
Hydrofluoric Acid: HF 6.3 x 10-4
Hypochlorous HClO 4.0 x 10-8
- PKa
- = -log Ka
- ______pKa is the ______acid ______
Sec 7.6 Acidity of Alcohols & Phenols
Alcohols:
- Alkoxide ion ______
- Acidity strength varies due to
- ______
- Size-must be ______
- Shape-Acidity of ______if same size
Phenols
- ______acids than alcohols
- Anion formed = ______
- Acidity when ______is stabilized by 1 of:
a) ______
b) ______
- Caused by ______on an adjacent carbon
- Ie: ______
- Ie: ______
- acidity when ______(Exception-______)
- Examples: Rank from lowest to highest acidity:
Basicity of Alcohols and Phenols
- ______bases
- Can be______by strong acids
- ______is used to initiate some alcohol reactions. Examples:
- ______
- ______
Comparison Alcohols to Phenols
- Difficult to break the ______during protonation (______difficult to form)
- ______
- ______
REACTIONS
DEHYDRATION of alcohols to alkenes
- Reaction summary:
STEPS:
- Ease of Rx: Easiest ______Hardest
- NOTE: Possible to have >= 2 alkene products as, the H+ can come from any adjacent C
- Zaitsev’s Rule: Most ______double bond predominates. (Greatest ______attached to the carbons of the double bond). Example:
ALKYL HALIDE FORMATION-1st method; w/HX X = Cl, Br, I
- Rx rate: ______
- Examples & steps:
ALKYL HALIDE FORMATION-2ND method; w/PX3
- Used w/______alcohols for ______
- Also produces a 2nd reaction product;______
- Has high ______& can be separated from the alkyl halide by ______
- Summary
Review of Phenol reactions: ______
Other Functional Groups to know:
- Carbonyl: Many variations-subgroups following
- Aldehyde:
- Ketone:
- Carboxylic Acid:
- Naming of carboxylic acids: Change the ”e” in the name of the alkane of the same length with the suffix –oic acid. The –COOH group is on carbon #1
- Examples:
- Ether
- Ester
- Formed in a 2-step process from alcohols;
- 1st the _____ of the alcohol is converted to a ______of a carboxylic acid
- 2nd the ______of the carboxylic acid is converted to an _____ group
- Naming of esters:
- 1st the R part of the –OR group is named R group name; methyl, ethyl, …
- 2nd use the name of the carboxylic acid, with the “ic” ending changed to “oate”
- Examples:
Which of the following is more oxidized? Why?
Special Alcohols:
- Glycol-______
Ethylene glycol: ______
- Glycerol-______Many derivatives of glycerol.
- Triglyceride: ______added to glycerol
- ______
- ______
- Formed w/______
- Phospholipids: 2 fatty acids & 1 phosphate group attached to glycerol
- ______
- Nitroglycerin: ______of glycerol
- ______
- ______
Nitration of Alcohols
REVIEW of nitration of phenol:
Oxidation of Alcohols
- Oxidation: ______
- The number of oxidation steps an alcohol can go through is ______
a) 1o alcohols go through the following oxidation steps: ______
_
b) 2o alcohols ______
c) 3o –______
- Oxidizing Reagents:
a) Jones’ Reagent: ______
b) PCC (pyridium chlorochromate): ______
- Example alcohol oxidation reactions:
- EtOH oxidation in the human body after drinking alcoholic beverages:
Oxidation of Special Phenols (2-OH groups)
- Produces ______called 1,4-______, sometimes 1,2
- Reversible to ______
- Quinones uses/functions:
a) ______
b) ______.
c) ______
d) ______
e) ______
Aromatic Substitution in Phenols
See page 133: OH- more ______than most except for _____, so OH- usually______
Phenols as Antioxidants
- ______are phenolic antioxidant ______
a) Destroy ______that cause ______
- ______natural antioxidant
a) Neutralizes (slows) ______
Thiols
- ______.
- Naming
a) like alcohol, ______
b) –SH is ______group
- Oxidation of thiols to disulfides:
- Disulfide significance:
a) ______
b) Create ______between ______within a protein molecule
used to ______
- Example Oxidation of Thiol problems:
Chap 7 Organic Chem Note Outline-Alcohols 5/14/19
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