Download Ch. 11: Carbon - Clark College

Ch. 11: Carbon
A Multifarious Element
Why Carbon?
• Versatility
• Single, double, triple bonds
• Structural diversity
Short-hand for expressing carbonbased compounds
• C4H10: butane
• Structural formula
• Condensed structural formula
• Carbon skeleton formula
• C4H8
• C4H6
Isomers
• Isomers – same composition, diff.
structures
• Structural isomers: same # atoms, diff.
structures
Ethanol (C2H6O) vs. dimethylether (C2H6O)
Problems
• Draw all isomers of C3H8O. There are 3.
• Draw all isomers of C4H8Br2. There are 9.
Stereoisomers
• Same formula, diff. orientation
• Two types:
• 1) geometric
• 2) optical isomers
Geometric isomers
• Require double bond!
• Cis vs. trans
Optical isomers
• Nonsuperimposable mirror images
• Called chiral molecules (chirality)
• Pairs of chiral molecules = enantiomers
Classes of Carbon-Containing
Cmpds
• Hydrocarbons
• Only C & H
• Alkane: CnH2n+2
• (Saturated every C-C bond single)
• Alkene: CnH2n (at least one double bond
btwn C’s)
• (Unsaturated  double, triple bonds)
Classes of Carbon-Containing
Cmpds
• Alkyne: CnH2n-2 (at least one triple bond
btwn C’s)
• Cyclohydrocarbons: rings of carbon
• Aromatic: rings w/pi-bonding
– benzene
Naming Alkanes
• Suffix: -ane
• Count out longest carbon chain
• Prefixes:
• 1C meth• 2C eth• 3C prop• 4C but• 5C pent• 6C hex• 7C hept• 8C oct• 9C non• 10C dec-
Naming Alkanes
• Hydrocarbon substitution = alkyl groups
• Meth  methyl, etc.
• Use number, followed by “-”, to designate placement of substituent
– 2-methylpentane
• If 2 or more of same subs.  di, tri, tetra, etc.
– 2,3-dimethylpentane
• If more than one different alkyl group, use alphabetic ordering
– Butyl precede ethyl precedes methyl
• 4-ethyl-3-methylheptane
• In naming hydrocarbons always go with longest carbon-chain
Draw out the following alkanes and
rename them, if needed
• Hexane
• 2-methylhexane
• 2,2-diethylpropane
• 4-ethyl-2-methylnonane
• Now, I’ll draw some and you name them
Naming Alkenes, alkynes
• Start counting carbon chain from lowest
carbon containing double/triple bond
• 1-propene, not 2-propene
• Use number, followed by “-”, to designate
placement of double or triple bond
– 1-butene
– 2-octyne
Draw the following and if there is
isomerism draw both structures
and name them
• 1-hexene
• 2-hexene
• 3-heptyne
• 2-methyl-3-heptyne
• Now, I’ll draw some and you name them
Naming Halohydrocarbons
• Same rules apply
–
–
–
–
–
In alphabetical order
Bromine  bromo
chlorine  chloro
fluorine  fluoro
iodine  iodo
• Ex: 2-chlorobutane
•
•
•
•
Practice (fix if necessary):
3-bromo-2-chloropentane
3,3-diiodobutane
Now, I’ll draw some and you name them
Naming Aromatic Cmpds
• Monosubstitution:
– Methylbenzene  toluene
– Phenol
– Aniline
• Disubstitution:
• o- = ortho
• m- = meta
• p- = para
Practice
• Chlorobenzene (does it make a difference
where you put the Cl?)
• Draw all isomers (and name them) of a
benzene that has 1 bromine and one
fluorine
– Which combinations are disallowed and why?
Other functional groups
• Functional group = characteristic grouping
or arrangement of atoms
• Alcohols = R-OH
• Methanol, ethanol, propanol, etc.
• Structural isomers of alcohols
• 1,2-ethanediol = ethylene glycol
Practice: rename if necessary
• 1-propanol
• 2-propanol
• 3-propanol
• Now, I’ll draw some and you name them
Other functional groups
• Ether: ROR’
1) Select the longest carbon chain and
name it as the correct alkane.
2) Change the “-yl” ending of the other
(shorter) hydrocarbon group to “-oxy” to
obtain the alkoxy group name.
3) Combine the two names giving the
alkoxy group name first.
Practice
• Dimethylether
• Butoxyhexane
• methoxyethane
• Now, I’ll draw some and you name them
Other functional groups
• Amines
• RNH2
• Putrescine = 1,4-butanediamine
• Cadaverine = 1,5-pentanediamine
Practice
• Triethylamine
• Triisopropylamine
• Now, I’ll draw some and you name them
Other functional groups
•
•
•
•
Aldehydes
RCOH
Start counting the carbon-chain from the C=O
Methanal, butanal, hexanal
•
•
•
•
Ketones
RCOR’
Start counting the carbon-chain from the C=O
2-propanone, 3-heptanone
Practice
• Methanal
• Hexanal
• 2-pentanone
• 4-decanone
• Now, I’ll draw some and you name them
Other functional groups
•
•
•
•
Carboxylic acids
RCOOH
Start counting the carbon-chain from the C=O
Methanoic acid, ethanoic acid, etc.
•
•
•
•
•
•
•
Esters
RCOOR’
Start counting the carbon-chain from the C=O
-OR’  takes on alkyl name
RCO  takes on –oate suffix
Thus, HCOOCH3  methyl methanoate
By the way, acetate = ethanoate
Practice
•
•
•
•
•
Hexanoic acid
2-methylpropanoic acid (give its other name)
Hexyl ethanoate
Butyl butanoate
3-methylbutyl ethanoate (has a more common
name)
• Now, I’ll draw some and you name them
Other functional groups
• Amides
• RCONR2
• Ex: methanamide, ethanamide
Polymers
• Huge molecules with repeating monomers
•
•
(subunits)
Thermoplastics (polyethylene, styrofoam):
respond to heating
Soften and flow when heated, harden when
cooled; reversible
– Over 60 million tons of polyethylene produced
annually!
• Thermosetting plastics (Formica-brand):
initially soft, but solid when heated; irreversible
Styrofoam, Teflon, silicone, Kevlar
Condensation Polymers
• Combining monomers and splitting out
small molecules (like water)
– Demo
• Making nylon
• Demo
– Green “snot”
Green “snot”
Copolymers
• Polymerization of 2
•
(or more) diff.
monomers
Such as:
– Styrene-butadiene
rubber (SBR)
• Predominately used for
car and light-truck tires