Transcript C - Issaquah Connect

CHAPTER 4: CARBON CHEMISTRY
 Organic
chemistry studies carbon
compounds; the backbone of biological
macromolecules
 When C forms four covalent bonds, its
hybrid orbitals create a tetrahedral shape.
 When 2 C’s are joined by a double bond, a
flat molecule forms
 The
electron configuration of carbon gives it
covalent compatibility with many different
elements.

What are some possibilities of molecules or compounds
that could form with the following molecules?
Figure 4.4
Hydrogen
Oxygen
Nitrogen
Carbon
(valence = 1)
(valence = 2)
(valence = 3)
(valence = 4)
H
O
N
C
CARBON BONDING
 Carbons
readily bond with each other;
they form single, double, triple, or
quadruple bonds
Name and
Comments
Molecular Structural
Formula
Formula
H
(a) Methane
CH4
H C
H
H
(b) Ethane
C2H6
H H
H C C H
H H
(c) Ethene
Figure 4.3 A-C (ethylene)
C2H4
H
H
C C
H
H
Ball-andStick
Model
SpaceFilling
Model
ISOMERS
 Isomers:
compounds with same molecular
formula but different structures & properties
1. Structural: differ in covalent arrangements of
atoms or double bond locations
2. Geometric (stereoisomers): differ in spatial
arrangements; have cis and trans arrangements
3. Enantiomers: mirror-image molecules
(a) Structural isomers
(b) Geometric isomers
H H H H H
H C C C C C H
H H H H H
X
H
C C
H
H C H
H C H
H
H
H C C C H
H H H
X
H
H
X
CO2H
(c) Enantiomers
Figure 4.7 A-C
H
C
CH3
C
C
X
H
CO2H
NH2 NH2
C
CH3
H
MORE ON GEOMETRIC ISOMERS
Cis isomer: has non-hydrogen atoms attached to
double bonded carbons on the same side of the
double bond.
 Trans isomer has these atoms on opposite sides of
the double bond

.
THALIDOMIDE:
--CONTAINS BOTH LEFT- AND RIGHTHANDED ISOMERS IN EQUAL AMOUNTS.
--THE (R) ENANTIOMER IS EFFECTIVE
AGAINST MORNING SICKNESS. THE (S)
CAUSES BIRTH DEFECTS.
--THE ENANTIOMERS CAN
INTERCONVERT
 Enantiomers
: L-Dopa is a drug used to treat
Parkinson’s…the drug’s enantiomer has no
effect on patients.
Figure 4.8
L-Dopa
D-Dopa
(effective against
Parkinson’s disease)
(biologically
inactive)
FUNCTIONAL GROUPS
 Functional
groups are
the parts of molecules
involved in
chemical reactions
 They are the
chemically reactive
groups of atoms
within an organic
molecule
 Give organic
molecules distinctive
chemical
properties Figure 4.9
Estradiol
OH
CH3
HO
Female lion
OH
CH3
CH3
O
Male lion
Testosterone

Six functional groups are important in the chemistry of
life






Hydroxyl
Carbonyl
Carboxyl
Amino
Sulfhydryl
Phosphate
 Study
and Learn Figure 4.10 in
your text
Some important functional groups of organic
compounds
HYDROXYL
CARBONYL
O
OH
(may be written HO
STRUCTURE
Figure 4.10
CARBOXYL
C
C
OH
)
A hydrogen atom is bonds
to an oxygen atom, which
in turn is bonded to the
carbon skeleton of the
organic molecule. (Do not
confuse this functional
group with the hydroxide
–
ion, OH .)
O
The carbonyl group
( CO) consists of a
carbon atom joined to
an oxygen atom by a
double bond.

When an oxygen atom is
double-bonded to a carbon
atom that is also bonded to a
hydroxyl group, the entire
assembly of atoms is called a
carboxyl group (—COOH).
SOME IMPORTANT FUNCTIONAL GROUPS OF
ORGANIC COMPOUNDS
Ketones if the carbonyl group
NAME OF
COMPOUNDS
Alcohols (their specific
names usually end in -ol)
EXAMPLE
H
H
H
C
C
H
H
is within a carbon skeleton
Aldehydes if the carbonyl
group is at the end of the
carbon skeleton
H
OH
Ethanol, the alcohol
present in alcoholic
beverages
H
Figure 4.10
H
H
C
H
C
H
H
Acetone, the simplest ketone
H
acids
O
C
H
Carboxylic acids, or organic
H
H
C
C
H
H
O
C
Propanal, an aldehyde
H
C
H
O
C
OH
Acetic acid, which gives vinegar its
sour taste
 Some
important functional groups of
organic compounds
AMINO
SULFHYDRYL
H
N
H
The amino
group (—NH2)
consists of a
nitrogen atom
Figure 4.10
bonded to two
hydrogen atoms
and to the
carbon skeleton.
PHOSPHATE
O
SH
(may be written HS
)
O P OH
OH
The sulfhydryl
group: a sulfur
atom bonded to a
hydrogen;
resembles a
hydroxyl group in
shape.
In a phosphate group, a
phosphorus atom is
bonded to four oxygen
atoms; one oxygen is
bonded to the carbon
skeleton; two oxygens
carry negative charges;
abbreviated P .