Transcript Functional Groups, etc.

Organic Chemistry I
The study of carbon-containing
compounds
Unit 1
A little bit of everything…
Oops!
 We are not starting at the
beginning of Chapter 1…
 because you need a little more time
with the concepts from the following
sections:
 2.12, 1.10, 1.11, 2.13, 2.14
Hydrocarbons
 Compounds that contain only H
and C atoms.
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alkanes (contain all single bonds)
alkenes (contain C=C)
alkynes (contain C≡C)
aromatics (contain a benzene ring)
Alkanes
 Each C atom is bonded to 4 other
atoms...why?
methane
CH4
nonane
CH3(CH2)7CH3
ethane
CH3CH3
decane
CH3(CH2)8CH3
propane
CH3CH2CH3
butane
CH3(CH2)2CH3
pentane
CH3(CH2)3CH3
hexane
CH3(CH2)4CH3
heptane
CH3(CH2)5CH3
octane
CH3(CH2)6CH3
Alkanes
 The most significant reaction of
alkanes is combustion.
 This is because alkanes do not have
any functional groups.
 Functional groups are where
reactions occur.
CH3(CH2)8CH3 + 15.5 O2(g)  10CO2(g) + 11H2O(l)
Showing the Structure of an
Organic Molecule
 You must be able to read and interpret
drawings of molecules from the start!
 structural formula = Lewis structure
 condensed (structural) formula
 line-angle formula
 3-dimensional formula
 (The molecular formula does not show
structure. It just gives numbers and
types of atoms.)
Molecular Formula, Lewis Structure,
and Condensed Structural Formula
The Lewis structure shows
all bonds and unbonded
valence electrons. Please
view the Lewis structures
PowerPoint on the 2114 web
page if you need a refresher.
These are all the same compound:
cis-hex-3-en-2-one
Condensed Structural Formula
• The atoms following the C are bonded to
the C:
CHCl2CH3
• Sometimes the atoms bonded to the
leading C are shown on the left:
H3CCH2CH3 or CH3CH2CH3
• The C is bonded to the C immediately
before it and the C atom immediately after
it…all C atoms in molecules have 4 bonds.
Condensed Structural Formula
• A group bonded to a C is shown in
parentheses, except on the last C.
CH3CH2CH2OH is 1-propanol
CH3CH(OH)CH3 is 2-propanol
• Typically, C=C and C≡C are shown,
but C=O is not.
CH3CH2CH=CHCOCH3
Line-Angle Structure
There is a C at the end of
every line segment and
enough H atoms to give
each neutral C four
bonds.
3-D Structure
 Solid lines are bonds in the
plane of the board or paper.
 Wedges show bonds to
atoms in front of the plane.
 Dashed lines show bonds to
atoms behind the plane.
Showing the Structure of an
Organic Molecule
 START NOW practicing
drawing these different types
of structures!
Functional Groups
 Functional groups are sites of
reactivity in an organic compound.
Is this compound
an alkane?
Is it a hydrocarbon?
It contains two
functional groups:
an alkene and a
ketone.
Functional Groups
 In hydrocarbons
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alkanes (no functional groups)
alkenes (contain C=C)
alkynes (contain C≡C)
aromatics (contain an aromatic ring,
the most common of which is the
benzene ring)
Two representations of a
benzene ring…it is NOT
classified as an alkene!
Functional Groups
 In hydrocarbons
Alkyl Substituents
 We look for the longest chain of C
atoms in the molecule.
 Groups of atoms attached to the C
atoms in the chain are called
substituents.
Alkyl Substituents
 When the substituent is an
alkane, it is called an alkyl group.
 The letter R is often used to
denote an alkyl substituent.
a methyl group
any alkyl group
Functional Groups
 In compounds containing O
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alcohols (R-OH)
ethers (R-O-R’)
ketones (contain C=O)
aldehydes (contain HC=O)
carboxylic acids (COOH)
carboxylic acid derivatives
 esters (RCOOR’)
 amides (RCONH2, RCONHR’, RCONR’R”)
 acid chlorides (RCOCl)
Functional Groups
 In compounds containing N
 amines (RNH2, RNHR’, RNR’R”)
 amides (RCONH2, RCONHR’,
RCONR’R”)
 nitriles (R-C≡N)
 In compounds containing X
 alkyl halides or haloalkanes
 X=halogen
Functional Groups-Alcohols (ROH) and Ethers (R-O-R’)
Functional Groups-Aldehydes
(HC=O) and Ketones (RC=OR’)
 C=O is a carbonyl group.
 C=O on the end of the carbon chain is an aldehyde.
 C=O elswhere in the carbon chain is a ketone.
Functional Groups-Carboxylic
Acids and Their Derivatives
 COOH is a carboxylic acid group.
 COOR is an ester.
 COCl is an acid chloride.
Functional Groups-Amines,
Amides, and Nitriles
 Amides are like amines, but with an adjacent C=O.
 Be careful! Both amines and amides have
different forms: primary (1°), secondary (2°), and
tertiary (3°).
 Nitriles are R-CN.
Primary (1°) Amines and
Amides
 A primary (1°) amine has one C atom (one
alkyl group R) and two H atoms bonded to
the N. The general formula is RNH2.
 A 1° amide has one acyl group and two H
atoms bonded to the N. The general
formula is RCONH2.
Secondary (2°) Amines and
Amides
 A secondary (2°) amine has two C atoms
(two alkyl groups) and one H atom
bonded to the N. The general formula is
RNHR’.
 A 2° amide has two C atoms (one in the
acyl group) and one H atom bonded to the
N. The general formula is RCONHR’.
Tertiary (3°) Amines and
Amides
 A tertiary (3°) amine has three C atoms
(three alkyl groups) and no H atoms
bonded to the N. The general formula is
RNR’R”.
 A 3° amide has three C atoms (one in the
acyl group) and no H atoms bonded to the
N. The general formula is RCONR’R”.
1°, 2°, 3° Amines and Amides
 Classify these.
Functional Groups - Alkyl
Halides
Cycloalkanes
are alkanes that
have a ring of C
atoms.
Classify the halides as 1°, 2°, or 3°.
Functional Groups
Circle and label each functional group.
fructose
threonine
γ-butyrolactone
(GBL)
acetaminophen
vitamin A
(retinol)