Occupy the Atom
Toronto French School alum
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3-methyl, 4-ethyl, heptane
This is one configuration of C10H22 , one of several
structural isomers.
Stick figures assume Cs at vertices and Hs where
no other bonds are marked.
Double bonds: molecule is “unsaturated”
A ‘saturated’ C has bonds to 4 different neighbours.
In an ‘unsaturated’ compound at least one C has fewer than 4
neighbours.
When there is a double bond the ‘ane’ ending of the hydrocarbon is
replaced by ‘ene’. If there is a triple bond, ‘yne’ is used instead.
H
H C
H
ethane
H
C H
H
H
H
H
C
ethene
Alkanes, alkenes and alkynes.
C
H
C
C
H
ethyne
“acetylene”
H
Isomers: cis vs. trans
cis
trans
Vs.
cis 2-butene
trans 2-butene
2-butyne
cyclohexane
1,3,5 cyclohexatriene
cyclohexa-1,3,5-triene
Special case of aromatic compounds
H
C
H
C
H C
H
C
C H
C
C
H
H
H
C
C H
H C
C
H
C
H
=
C
C H
C
H
C
H C
C H
C
C
H
H
C
H C
H
H
H
=
H
C
molecule module
ethane
ethyl
benzene phenyl
C
H
The modules that make up a molecule contribute to
its chemical and physical properties.
This is why knowledge of the structure provides
insight into the behaviour of the chemical.
Heteroatoms= any atom that is not C or H.
H3C
H O
CH2
H3C
H
HN
CH2
H3C
CH3
C2H6 gas at 25 °C, not soluble in water.
HO
CH2
H3C
C2H5OH liquid, soluble in water.
C2H5NH2 gas, pungent, corrosive.
H2N
CH2
H3C
Alcohols
R-OH (R = ‘whatever’)
More soluble in water than the parent hydrocarbon.
lower boiling point “ “ “
We value ethyl alcohol for its relaxing and inebriating
effects, but other alcohols can be toxic or otherwise
dangerous. This is just a module that can appear as part
of very diverse molecules.
R
Primary alcohols R-CH2OH
Secondary alcohols R,R’CHOH
C
H2
OH
R CH
R'
OH
Aromatic alcohols are weakly acidic
Fig 12.13
Antiseptic: kills bacteria, acidity and solvent of
membrane lipids
BPA: bis-Phenol A
2,2-bis(4-hydroxyphenyl)propane
http://en.wikipedia.org/wiki/Bisphenol_A
Ethers
R-OR‘
(R’ = ‘another whatever’)
Fig 12.15
Can H-bond,
Cannot H-bond
this is considered to be more drastic than
two different configurations of an alkane.
Fig 12.16
Ethers in your day
O
O
O
diethyl ether: anaesthetic
OH
dioxane, solvent, pollutant
O
O
O
OH
PEG = poly ethylene glycol (check your shampoo &
toothpaste).
Carbonyl group: >C=O
Internal carbonyl:
ketone
Nail polish
remover.
Terminal carbonyl:
aldehyde
The C also
has a bond
to an H.
Fragrant aldehydes (even acetone smells ‘nice’)
Carboxylic acids: R-COOH
It’s back !!! Acetic acid :
O
O
+ H+
OH
O-
carboxylic acid
carboxylate
Formic acid
O
O
HC
HC
OH
+ H+
O-
Butane’s acid: butanoic acid: CH3CH2CH2COOH
Esters R-COO-R’
O
O
O
ethylbutyrate
ethylbutyrate
ethyl butyl ether
O
essence of pineapple
O
Still one of the safest drugs known
condensation with
loss of water
+
HO
H2O
+
O
acidic phenol in
addition to carboxyl
Mask phenol by
forming an ester