Chapter 13 Alcohols, Phenols, Ethers; Thiols and Sulfides
C C
H
H
OH
H
H
H C O C
H
H
H
H
H
H
AlcoholOH attached to sp3 carbon
EtherOxygen attached to two carbons
Ethanol bp = 74 °C
Dimethyletherbp = -27 °C
Fig. 13-1, p. 505
Alcohol introduction: Hydrogen Bonding
Alcohol introduction: Types of Alcohols
H C
H
H
OH H C
H
R
OH R C
H
R
OH R C
R
R
OH
R = sp3 carbon
methyl 1° 2° 3°
Alcohol introduction: reaction of sp3 oxygen with strong acids
H OH HCl+
H C
H
H
OH HCl+
C O C
H
H
H
H
H
H HCl+
Table 13-1, p. 506
Fig. 13-2, p. 508
Fig. 13-2, p. 508
[elim]
[sub] [sub]
Reactions
I. Substitution Reactions of Alcohols (review)
A. Conversion to alkyl halides
1. 1° & 3° with strong acid
Reactions
I. Substitution Reactions of Alcohols (review)
A. Conversion to alkyl halides
1. 1° & 3° with strong acid
Reactions
I. Substitution Reactions of Alcohols (review)
A. Conversion to alkyl halides
1. 1° & 3° with strong acid
2. 1° & 2° with SOCl2, pyridine
3. 1° & 2° with PBr3
.
p. 516
Substitution Reactions of alcohols : review
Reactions
I. Substitution Reactions of Alcohols (review)
A. Conversion to alkyl halides
1. 1° & 3° with strong acid
2. 1° & 2° with SOCl2, pyridine
3. 1° & 2° with PBr3
4. 1° & 2° with TsCl
Reactions
I. Substitution Reactions of Alcohols (review)
A. Conversion to alkyl halides
1. 1° & 3° with strong acid
2. 1° & 2° with SOCl2, pyridine
3. 1° & 2° with PBr3
4. 1° & 2° with TsClProblem: Enantiomeric products from same starting
material.
I. Substitution Reactions of Alcohols (cont.)
B. Formation of alkoxide ions
• pKa’s of alcohols
Reactions
Table 13-1, p. 506
I. Substitution Reactions of Alcohols (cont.)
B. Formation of alkoxide ions
• pKa’s of alcohols
1. Strong Bases (NaH, NaNH2)
2. Metals (Na0)
Reactions
I. Substitution Reactions of Alcohols (cont.)
B. Ether formation
1. Williamson Ether Synthesis
a. Formation of alkoxides
b. acyclic ethers
c. cyclic ethers (including
oxiranes)
2. Acid catalyzed ether formation
Reactions
I. Substitution Reactions of Alcohols (cont.)
C. Protection
1. introduction to protection
a. TMS ether
Reactions
II. Reactions of ethers.
A. Unstrained
B. Oxiranes (epoxides)
1. basic / nucleophilic conditions
•epoxy resins (what is in those two
tubes)
Reactions
Epoxy Resins
Epoxy ResinsTwo substances
Substance #1. diepoxy prepolymer.
C
CH3
CH3
O O C C
H
H
C
H
H
CH
O
H2C
OH
H
C
H
H
O C
CH3
CH3
O C
H
H
CH
CH2
O
n = 0 - 25epoxide epoxide
Epoxy ResinsTwo substances
Substance #1. diepoxy prepolymer.
C
CH3
CH3
O O C C
H
H
C
H
H
CH
O
H2C
OH
H
C
H
H
O C
CH3
CH3
O C
H
H
CH
CH2
O
n = 0 - 25epoxide epoxide
H2C CH
C
H
H
O C
CH3
CH3
O C
H
H
CH
CH2
O
n = 0
O
Epoxy ResinsTwo tubes
Substance #1. diepoxy prepolymer.
Substance #2. A polyamine (hardener, curing agent)
C
CH3
CH3
O O C C
H
H
C
H
H
CH
O
H2C
OH
H
C
H
H
O C
CH3
CH3
O C
H
H
CH
CH2
O
n = 0 - 25epoxide epoxide
H2C CH
C
H
H
O C
CH3
CH3
O C
H
H
CH
CH2
O
n = 0
O
H2N
HN
NH2
II. Reactions of ethers.
A. Unstrained
B. Oxiranes (epoxides)
1. basic / nucleophilic conditions
•epoxy resins (what is in those two
tubes)
2. acidic conditions
a. 1° & 2°
b. 3°
Reactions
II. Reactions of ethers.
A. Unstrained
B. Oxiranes (epoxides)
1. basic / nucleophilic conditions
•epoxy resins (what is in those two tubes)
2. acidic conditions
a. 1° & 2°
b. 3°
C. Allyl Aryl Ethers (The Claisen Rearrangement)
Reactions
Professor Rainer Ludwig Claisen (January 14, 1851 – January 5, 1930) was a famous German chemist best known for his work with condensations of carbonyls and sigmatropic rearrangements. He was born in Cologne as the son of a jurist and studied chemistry at the university of Bonn under August Kekulé, where he became a member of K.St.V. Arminia. He served in the army as a nurse in 1870-1871 and continued his studies at Göttingen University until he returned to the University of Bonn in 1872. He started his academic career at the same university in 1874. During his career he worked with other notable chemists, including the Noble Laureates Adolf von Baeyer and Emil Fischer. He died in 1930 in Godesberg am Rhein. In addition to the Claisen (1887) and Claisen-Schmidt (1881) condensations, the Claisen rearrangement (1912) and the Claisen isatin synthesis (1879), his name is associated with the Claisen flask and Claisen's rule which relates acidity to enolisation.
http://www.chem.qmul.ac.uk/rschg/biog.html
Reactions
III. Preparation of alcohols
From Alkenes (review)
1. Hydration (section 8.4)
a. H2O + HX (Markovnikov)
b. Oxymercuration (Markovnikov)
c. Hydroboration & oxidation (anti-
Markovnikov)
p. 509
Synthesis of alcohols : review
IV. Reduction and Oxidation reactions
• oxidation states
Reactions
Fig. 13-2, p. 508
Fig. 13-2, p. 508
[elim]
[sub] [sub]
Fig. 13-2, p. 508
[red]
[red][red]
[red]
Fig. 13-2, p. 508
[ox]
[ox]
[ox]
[ox]
V. Reduction and Oxidation reactions
• oxidation states
A. Alcohols From Carbonyl Compounds (reduction)
1. Hydride Reducing Agents
2. Grignard Reagents
i. TMS protection
Reactions
p. 557
Fig. 1, p. 557
V. Reduction and Oxidation reactions
• oxidation states
A. Alcohols From Carbonyl Compounds (reduction)
1. Hydride Reducing Agents
2. Grignard Reagents
B.Alcohols To Carbonyl Compounds (oxidation)
1. CrO3, H2SO4
2. K2Cr2O7
3. PCC
4. Dess – Martin Periodinane
Reactions
A better way to oxidize alcohol?
Cr(VI) reagents: 3–10 mg acutely poisonous for a 150-lb adult.
An investigation into an illegal release of Cr(VI) into drinking water was the basis of the film Erin Brockovich.
Chemical Reaction
2 K2Cr2O7 + 3 CH3CH2OH + 8 H2SO4
2 Cr2 (SO4)3 + 2 K2SO4 + 3 CH3COOH + 11 H2O
AgNO3
Fig. 13-9, p. 536
Spectroscopy of alcohols : Infrared
Fig. 13-10, p. 536
Spectroscopy of alcohols : Infrared
Fig. 13-11, p. 537
Spectroscopy of alcohols : NMR
p. 552
C5H10O
Fig. 13-12, p. 538
Spectroscopy of alcohols : Mass Spec
