AlkanesAlkanes
Alkanes:Alkanes: hydrocarbons hydrocarbons containing only carbon-containing only carbon-carbon single bondscarbon single bondsthe first two alkanes are the first two alkanes are methane and ethanemethane and ethane
Hydrocarbon:Hydrocarbon: a a compound composed of compound composed of
only carbon and only carbon and hydrogenhydrogen
AlkanesAlkanes
the first 10 alkanes with the first 10 alkanes with unbranched chainsunbranched chains
Generic Alkane Formula: CnH2n+2
Constitutional IsomerismConstitutional Isomerism
Constitutional isomers:Constitutional isomers: compounds that have the compounds that have the same molecular formula same molecular formula but different structural but different structural formulas (connected formulas (connected
differently)differently)
Constitutional IsomerismConstitutional Isomerism
CH3CH2CH2CH3 CH3CHCH3
CH3
Butane(bp -0.5°C)
2-Methylpropane(bp -11.6°C)
sameconnectivity
Stereoisomers
Chiral
Enantiomers Diastereomers
Constitutional Isomers
Cis-Trans Isomers
withstereocenters
without stereocenters
Achiral
differentconnectivity
Isomers
Map of Organic Map of Organic IsomerizationIsomerization
CycloalkanesCycloalkanes
Cyclic hydrocarbon: a hydrocarbon that a hydrocarbon that
contains carbon contains carbon atoms joined to atoms joined to
form a ringform a ring
Alkenes and AlkynesAlkenes and Alkynes Alkene:Alkene: a hydrocarbon that a hydrocarbon that
contains one or more carbon-contains one or more carbon-carbon double bondscarbon double bonds ethylene is the simplest alkeneethylene is the simplest alkene
H
C C
H
H H
H-C C-H
Acetylene(an alkyne)
Ethylene(an alkene)
Alkenes and AlkynesAlkenes and Alkynes AlkyneAlkyne:: a hydrocarbon that a hydrocarbon that
contains one or more carbon-contains one or more carbon-carbon triple bondscarbon triple bonds acetylene is the simplest alkyneacetylene is the simplest alkyne
H
C C
H
H H
H-C C-H
Acetylene(an alkyne)
Ethylene(an alkene)
AlkenesAlkenes Cis-trans isomerismCis-trans isomerism
because of restricted rotation about because of restricted rotation about a carbon-carbon double bond, an a carbon-carbon double bond, an alkene with two different groups on alkene with two different groups on each carbon of the double bond each carbon of the double bond shows cis-trans isomerismshows cis-trans isomerism
trans-2-Butenemp -106°C, bp 1°C
cis-2-Butenemp -139°C, bp 4°C
HC C
CH3
H3C H
HC C
H
H3C CH3
Aromatic CompoundsAromatic Compounds Aromatic compound:Aromatic compound: a a
hydrocarbon that contains one hydrocarbon that contains one or more benzene-like ringsor more benzene-like rings arene:arene: a term used to describe a term used to describe aromatic compoundsaromatic compounds
Ar-Ar-:: a symbol for an aromatic a symbol for an aromatic group derived by removing an -H group derived by removing an -H from an arenefrom an arene
Nomenclature ExampleNomenclature Example
CH3NO2
Cl
OH
Br
BrBrNO2
CH2CH3
Br
43
2
1
5
6
43
21
43
1 2
4-Chloro-2-nitrotoluene
2,4,6-Tribromophenol 2-Bromo-1-ethyl-4-nitrobenzene
Functional Functional Groups and Groups and Reactions of Reactions of
Organic Organic CompoundsCompounds
AlkanesAlkanes
They burn!They burn! Hydrocarbon Hydrocarbon
and Oxygen and Oxygen yields Carbon yields Carbon Dioxide and Dioxide and WaterWater
Reactions of Alkenes:Reactions of Alkenes:ADDITION REACTIONSADDITION REACTIONS
Alkenes are Alkenes are unsaturatedunsaturated — more — more bonds can form to the C atomsbonds can form to the C atoms
Molecules such as BrMolecules such as Br22, H, H22, HCl, HBr, , HCl, HBr,
and Hand H22O O addadd to the double bond to the double bond
C CCH
H
H
HC
Br BrH H
HH
+ Br2
1,2-dibromoethane
C CCH
H
H
HC
Br BrH H
HH
+ Br2
1,2-dibromoethane
An Addition An Addition ReactionReaction
The fat in bacon is partially The fat in bacon is partially unsaturated. The fat adds unsaturated. The fat adds
BrBr22 to the C=C bonds. to the C=C bonds.
An Addition ReactionAn Addition Reaction Fats can be “hydrogenated” with HFats can be “hydrogenated” with H22..
Peanut butter has partially Peanut butter has partially hydrogenated vegetable oil.hydrogenated vegetable oil.
Peanut butter has partially Peanut butter has partially hydrogenated vegetable oil.hydrogenated vegetable oil.
Saturated Fats
Reactions of AromaticsReactions of Aromatics SubstitutionsSubstitutions — not additions — not additions
— are typical.— are typical.
AlClAlCl33 is a catalyst. Catalysts typically is a catalyst. Catalysts typically
used in aromatic substitutions.used in aromatic substitutions.
+ CH3Cl
CH3
+ HClAlCl3
Functional GroupsFunctional Groups
See CD-ROM Screens 10.5 & 10.6See CD-ROM Screens 10.5 & 10.6See CD-ROM Screens 10.5 & 10.6See CD-ROM Screens 10.5 & 10.6
AlcoholsAlcohols Characterized by –OH group Characterized by –OH group
[R-OH[R-OH Name: add – ol to name of Name: add – ol to name of
hydrocarbonhydrocarbon
MethanolButanol
Structures of AlcoholsStructures of AlcoholsCC33HH55OH: how many structural isomers?OH: how many structural isomers?
C C C OH
H
H
H
H
H
H
H
1-propanol
C C C H
H
H
OH
H
H
H
H
2-propanol
Add -ol to name of 3-C hydrocarbon. Add -ol to name of 3-C hydrocarbon. Indicate position of OH with number.Indicate position of OH with number.
Alcohol PropertiesAlcohol Properties Alcohols are a derivative of water Alcohols are a derivative of water Many alcohols dissolve in waterMany alcohols dissolve in water
Methanol Methanol dissolves in water.dissolves in water.Methanol Methanol dissolves in water.dissolves in water.
Butanol is NOT Butanol is NOT soluble in water. soluble in water. Butanol is NOT Butanol is NOT soluble in water. soluble in water.
““SternoSterno””
Alcohols burn in air Alcohols burn in air
A mixture of A mixture of
ethanol + calcium ethanol + calcium
acetate = STERNOacetate = STERNO
GLYCOLSGLYCOLSAlcohols with Two OH Alcohols with Two OH
GroupsGroups
Propylene Propylene glycolglycol
EthyleneEthylene glycolglycol
Sugars: Related to Sugars: Related to AlcoholsAlcohols
Sugars are carbohydrates, compounds Sugars are carbohydrates, compounds with the formula Cwith the formula Cxx(H(H22O)O)yy..
O
H
HO
H
HO
HOHH
OH
OHCHO
OHH
HHO
OHH
OHH
CH2OH
O
H
HO
H
HO
OHOHH
H
OH
1
23
4 5
12
3
45
1
2
3
4
5
-D-glucose -D-glucose
Open chain form
H H
AminesAminesAminesAminesAlcohols are derivatives of HAlcohols are derivatives of H22OO
(R–OH) and (R–OH) and aminesamines are are derivatives of NHderivatives of NH33..
MethylamineMethylamine Dimethylamine TrimethylamineTrimethylamine
AminesAminesAminesAminesAmines generally have terrible Amines generally have terrible
odors!odors!
CadaverineCadaverinePyridinePyridine
AminesAminesAminesAminesAmines, like NHAmines, like NH33, are bases, are bases
2 C6H5NH2 (aq) + H2SO4(aq) 2 C6H5NH3+(aq) + SO4
2-(aq)
Aniline Anilinium ion
AminesAminesAminesAmines Many natural Many natural products products and drugs and drugs (such as (such as
nicotine and nicotine and cocaine) are cocaine) are
bases.bases.
NicotineNicotine
Structures of Structures of AldehydesAldehydes
CinnamaldehydeCinnamaldehydeOdors from Odors from
aldehydes and aldehydes and ketonesketones
Carboxylic AcidsCarboxylic AcidsBenzoic acidBenzoic acid
Carboxylic acid group Carboxylic acid group with acidic Hwith acidic H++
All are All are WEAKWEAK acids acids
Acetic acidAcetic acid
Acids are found in Acids are found in many natural many natural substances: bread, substances: bread, fruits, milk, winefruits, milk, wine
Acids are found in Acids are found in many natural many natural substances: bread, substances: bread, fruits, milk, winefruits, milk, wine
CarboxylCarboxylic Acidsic Acids
Formic acid, HCOFormic acid, HCO22H, H,
gives the sting to ants.gives the sting to ants.
Formic acid, HCOFormic acid, HCO22H, H,
gives the sting to ants.gives the sting to ants.
Acids + Alcohols --> Acids + Alcohols --> ESTERSESTERS
Esters have generally pleasant odorsEsters have generally pleasant odors
Acids + Alcohols --> Acids + Alcohols --> ESTERSESTERS
H+
O O
CH3COH + CH3CH2OH CH3COCH2CH3 + H2O
Acetic acid Ethanol Ethyl acetate
Acids + Alcohols --> Acids + Alcohols --> ESTERSESTERS
O
RC —O —HH+
O
+ R'—O —H RC —O —R' + H2O
Carboxylic acid Alcohol Ester
C
OC
O O
H
O
CH3Aspirin, Aspirin, acetylsalicylic acid,acetylsalicylic acid,
Acid and EsterAcid and Ester
Fats and OilsFats and OilsFats with C=C bonds are usually LIQUDSFats with C=C bonds are usually LIQUDSFats with C=C bonds are usually LIQUDSFats with C=C bonds are usually LIQUDS
Oleic acid: a Oleic acid: a monounsaturated monounsaturated fatty acid fatty acid
Oleic acid: a Oleic acid: a monounsaturated monounsaturated fatty acid fatty acid
C=C BondC=C Bond
Fats and OilsFats and Oils
Fats with saturated acids (no C=C bonds) Fats with saturated acids (no C=C bonds) are SOLIDS.are SOLIDS.
Fats with saturated acids (no C=C bonds) Fats with saturated acids (no C=C bonds) are SOLIDS.are SOLIDS.
Saturated fats Saturated fats are more are more
common in common in animals. animals.
Saturated fats Saturated fats are more are more
common in common in animals. animals.
Trans Fatty AcidsTrans Fatty Acids•Oleic acid is a mono–Oleic acid is a mono–unsaturated cis-fatty acidunsaturated cis-fatty acid•Trans fatty acids have Trans fatty acids have deleterious health effects. deleterious health effects. •Trans fatty acids raise plasma Trans fatty acids raise plasma LDL cholesterol and lower HDL LDL cholesterol and lower HDL levels.levels.
Acids + Amines --> Acids + Amines --> AMIDESAMIDES
AcetoaminophenTylenol, Datril, Momentum, ...AcetoaminophenTylenol, Datril, Momentum, ...
C
C
C
C
C
C
H
H
N
H
O
HCC
O
H
HH
H
H
Amide link
PolymersPolymersPolymersPolymers Giant molecules made by joining Giant molecules made by joining
many small molecules called many small molecules called monomersmonomers
Average production is 150 kg per Average production is 150 kg per person annually in the U.S.person annually in the U.S.
Polymer Classifications
ThermoplasticsThermoplastics (polyethylene) soften and (polyethylene) soften and flow when heatedflow when heated
ThermosettingThermosetting plastics — plastics — soft initially but set to soft initially but set to solid when heated. solid when heated. Cannot be resoftened.Cannot be resoftened.
Polymer Classifications
Other classification: Other classification: plastics, fibers, plastics, fibers, elastomers, elastomers, coatings, adhesivescoatings, adhesives
Polymer Preparation
Addition polymers — polymers — directly adding monomer directly adding monomer units togetherunits together
Condensation polymers — polymers — combining monomer units combining monomer units and splitting out a small and splitting out a small water (water)water (water)
Polyethylene: Addition Polymer
H2C CH2 C C
H
H
H
H
n
n
EthyleneEthylene PolyethylenePolyethylene
A polymer with a molar A polymer with a molar mass of a million has mass of a million has
about 36,000 units.about 36,000 units.
Mechanism of Addition
Polymerization
Addition Polymerization
1.1. InitiationInitiation
2.2. AdditionAddition
3.3. PropagationPropagation
4.4. TerminationTermination
Types of Polyethylene
Linear, high Linear, high density PE (HDPE)density PE (HDPE)
Branched, low Branched, low density PE, LDPEdensity PE, LDPE
Cross-linked Cross-linked PE, CLPEPE, CLPE
Types of Polyethylene
CH2CH
OH
CH2CH
OCCH3
CH2CH
n n n
polyvinyl alcohol polyvinyl acetate polystyrene
Polymers based on Substituted Ethylenes, CH2=CHX
O
Table 11.12: others are PVC, Table 11.12: others are PVC, acrylonitrile, polypropylene, polymethyl acrylonitrile, polypropylene, polymethyl
methacrylatemethacrylate
Polystyrene
Polystyrene is nonpolar material and Polystyrene is nonpolar material and dissolves in organic solvents.dissolves in organic solvents.
PS foam is mostly air, and when it PS foam is mostly air, and when it dissolves it collapses to a much smaller dissolves it collapses to a much smaller volume.volume.
Condensation
PolymersHOC
O
COH
O
CO
COCH2CH2OO
+ n HOCH2CH2OH
terephthalic acid ethylene glycol
+ H2 O
Polyethylene terephthalate (PET), a polyester
n
n
Polyesters, PET
Jackets made from recycled Jackets made from recycled PET soda bottlesPET soda bottles
Soda bottles, mylar Soda bottles, mylar film.film.
Polyamides: Nylon
•Each monomer has 6 C atoms in its chain.Each monomer has 6 C atoms in its chain.•A polyamide link forms on elmination of HClA polyamide link forms on elmination of HCl•Result = nylon 66Result = nylon 66•Proteins are Proteins are polyamidespolyamides