Transcript Alcohols and Phenol - Belle Vernon Area School District

Chapter 4
• Covalent bonds can be either polar or non
polar
• Polar – covalent bonds with equal sharing
of e-’s
• Non-Polar – covalent bonds with unequal
sharing of e-’s
• Always form nonpolar molecules
• Equal distribution of electrons
•No charged areas
• In symmetrical molecules  nonpolar
molecules
•Bonds are equidistant from each other if
symmetric
• In unsymmetrical molecules polar
molecules
•Charged areas due to uneven edistribution
σ+
σ-
H – Cl
• Nonpolar molecules are held
together by LDF (attractions between
temporary dipoles and induced
dipoles)
•Induced dipoles – temporary dipoles
formed by the attraction of one atoms
nucleus for another atom’s e-’s
• Dipole-Dipole attractions
•Attraction between oppositely charged
poles on 2 polar molecules
• Hydrogen Bonds (very strong dipole-dipole)
•The attraction between the + charges H
on one dipole and the – charged highly
e-neg element in the polar molecule.
• Order of strength…
• H-Bond>dipole-dipole>LDF
• Both alcohols and phenol contain OH
• OH – Hydroxyl group
• Alcohol  General Formula = R-OH
• Phenol  General Formula = Ar-OH
• The difference between alcohols and
phenol is the O added to make the
OH group
• Results in 3 differences…
• 1. Alkanes = nonpolar molecules with
LDF
• Alcohols = have polar areas and H
Bonding
•C–C–C–OH
σ- σ+
Nonpolar
Region
• 2. Alkanes cannot dissolve in H2O
while shorter (2-5 C’s) alcohols can
• 3. Alcohols have higher boiling points
that their corresponding alkanes
• C = -162 °C
• C-C = -88.5 °C
• C-C-C = 0 °C
C-OH = 64.5 °C
C-C-OH = 78.3 °C
C-C-C-OH = 118 °C
• 1° alcohol – hydroxyl group on 1° C
C-C-C-OH
• 2° alcohol – hydroxyl group on 2° C
C-C-C
OH
• 3° alcohol – hydroxyl group on 3° C
C
C-C-C
OH
1. Drop –e from the alkane & add –ol
2. # from end closest to –OH & add
the # in front of the “main”chain
3. The –OH has priority over other
functional groups covered
• C-C-C-OH
OH
• C-C-C-C-C-C-C
OH
OH
• C-C-C-C
C-C-C-C-C-C-OH
OH
OH OH
C-C-C-C-C
Cl OH
C OH
• C-C-C-C
C-C-C-C-C-C
Br
Br Br OH
• C-C-C-C-C-C-C-C-C
OH
OH
• C-C-C-C-C
C-C-C-C-C
OH OH
• C-C-C-C-C-C-C
OH OH OH
• C-C-C-C-C-C
Cl
OH
Cl
C-C-C-C-C-C-C
C-C
1. 1°Alcohols
a.) Alkyl halide + water  alcohol + hydrogen halide
RX
+ H2O  R-OH + HX
Form 1-Propanol (str & cond)
Cl
OH
C-C-C + H2O  C-C-C + HCl
CH3CH2CH2Cl + H2O  CH3CH2CH2OH + HCl
• React ethylfluoride with water
(str,cond, name product)
b.) Alkyl + metal  alcohol + metal
halide hydroxide
halide
RX + M+OH-  ROH + MX
(M Can be Li+,Na+,or K+)
• Form Heptanol (str and Cond)
(you can choose any of the 3 metals – Na is
most common)
C-C-C-C-C-C-C-Cl + NaOH 
C-C-C-C-C-C-C-OH + NaCl
CH3(CH2)5CH2Cl + NaOH  CH3(CH2)5CH2OH + NaCl
• React methyl bromide with potassium
hydroxide
• Synthesize – to form an organic compound
from the pure hydrocarbon (usually needs
more than one step)
• Synthesis of a 1° Alcohol requires 2 steps
1. RH + Cl2  RCl + HCl
2. RCl + H2O (or NaOH)  ROH + HCl
Na could be Li or K
(or NaCl)
• Synthesize methanol (str)
1. C + Cl2  CCl + HCl
2. CCl + NaOH (or H2O)  COH + NaCl
(or HCl)
• Synthesize 1-Pentanol (condensed)
CH3(CH2)3CH3 + Cl2  CH3(CH2)3CH2Cl + HCl
CH3(CH2)3CH2Cl + KOH (or H2O) 
CH3(CH2)3CH2OH + KCl (or HCl)
1. Alkene + water  2° or 3° Alcohol
Hydrate 3-ethyl-2-pentene
(str,cond,name prdct)
2. RX + H2O  ROH + HX
• React 3-iodoheptane with water (str,
cond, name product)
3. RX + M+OH-  ROH + MX
React 2-fluoropropane with Lithium
Hydroxide (str, cond, name product)
• Form 2-hexanol 3 ways (str)
• Form 3-octanol 3 ways (cond)
• Synthesize 2 - Butanol
1. Halogenation (same as alkanes)
R-OH + X2  R-XOH + HX
Form 3-bromo-1-heptanol (3bromoheptanol) (str and cond)
Br
C-C-C-C-C-C-C-OH +Br2  C-C-C-C-C-C-C-OH
• Form 1,2,2,3-tetrafluorohexanol
(*1-hexanol) (str&cond)
Form 3-iodo-3-hexanol (str&cond)
2. Alcohol + hydrogen halide  alkyl
halide + water
ROH + HX RX + H2O
React methanol with hydrogeniodide
(str, cond, name product)
CH3-OH + HI  CH3-I + H2O
• React 2-pentanol with Hydrogen
Fluoride (str, cond, name product)
3. Dehydration of alcohols to form
alkenes
Alcohol –H2SO4alkene + H2O
Dehydrate 2-butanol (str&cond)
OH
C-C-C-C –H2SO4C=C-C-C + H2O
• Reaction Mechanism for Dehydration
of Alcohols
H
•
• C-C-OH + H+  C-C-O-H+
•
H
• C-C-O-H+  C-C+ + H2O
• C-C+  C=C + H+
•H
Indicated Protonated Alcohol
• Protonated alcohol – an alcohol
where a H+ bonds coordinately to the
hydroxyl group giving the alcohol a
positive charge
4. Alcohol + metal  alcohol salt + H
ROH + M  RO-M+ + ½ H2
*M = Na+, K+, Ba+2, Ca+2, Mg+2, Al+3
• React ethanol with Barium
• C-C-OH + Ba  (C-C-O-1)2Ba+2 + H2
• Condensed:
1. Name Metal
2. Prefix for # of C’s and follow with
– oxide
(C-C-O-1)2 Ba+2 = barium ethoxide
• React pentanol with lithium (str, cond,
name product)
2-C-C-C-C-C-OH + 2Li  2C-C-C-CC-O-1Li+ + H2
(Coefficient for H2 groups at the end)
Condensed:
Name:
• React methanol with Al (str, cond,
name product)
• Synthesize barium octoxide (cond.)
5. Alcohol + metal hydroxide  alcohol salt + water
ROH + M+1OH-1  RO-M+ + H2O
React ethanol with lithium hydroxide
(str,cond, name product)
C-C-OH + LiOH  C-C-O-1Li+ + H2O
Lithium ethoxide
• React propanol with Mangesium
hydroxide [Mg(OH)2] (balance it)
• React pentanol with aluminum
hydroxide (balance it)
• Form barium nonoxide 2 ways
(condensed)
• General form: ArOH
C6H5OH
• Nomenclature: Orthobromophenol or
2-bromophenol (-OH = #1 position)
2,3 – dibromophenol
• ArCl + H2O or NaOH  ArOH + HCl or NaCl
• Synthesis of phenol:
ArH + Cl2 –FeCl3 ArCl + HCl
ArCl + H2O or NaCl  ArOH + HCl or
NaCl
Do synthesis structurally
1. Halogenation:
ArOH + X2 –FeX3 ArXOH + HX
Form 2,4-diiodophenol
2. Nitration:
ArOH + HNO3 –H2SO4ArNO2OH + H2O
Form 2,3,5-trinitrophenol
3. Friedel-Crafts Alkylation:
ArOH + RCl –AlCl3 ArROH + HCl
Form metapropylphenol
4. Phenol + metal  phenol salt +
hydrogen
ArOH + M  ArO-1M+ + ½ H2
React phenol with Lithium
(need 2 rxn groups to make H2)
5. Phenol + metal hydroxide  phenol
salt + water
ArOH + M+OH-  ArO-M+ + H2O
React phenol with barium hydrxide
• Synthesize aluminum phenoxide
(str&cond)
1.
+ Cl2 –FeCl3
+ HCl
2.
+ H2O or NaOH 
+ HCl
or NaCl
Either…
3. 6
+ 2Al  2 (
3. 3
+ Al(OH)3 (
O-)3Al+3 + 3H2
O-)3Al+3 + 3H2O