Chapter 1 1

ORGANIC CHEMISTRY

STUDY OF CARBON -CONTAINING COMPOUNDS

Chapter 1 2

SHORT HISTORY OF CHEMISTRY

PRE-1828 ERA

TWO MAJOR DISCIPLINES EMERGING

INORGANIC - MINERAL CHEMISTRY

ORGANIC CHEMISTRY - PLANTS AND ANIMALS

Chapter 1 3

ORGANIC COMPOUNDSCHARACTERISTIC PRODUCTS OF LIVING ORGANISMS

SUBSTANCES LIKE SUGAR AND OLIVE OILINORGANIC COMPOUNDS

PRODUCTS FROM NON-LIVING ENVIRONMENT

SUBSTANCES LIKE WATER AND IRON

BERZILIUS’ DEFINITIONS

Chapter 1 4

Woehler’s urea synthesis

Ammonium isocyanate + heat ------> urea

NH4CNONH2CONH2

“I have been able to make urea without aid of kidneyof man or dog.

1828

1828

Chapter 1 5

Liszt - Old

Chapter 1 6

BIRTHSJULES VERNE - AROUND THE WORLD IN 80 DAYS

LEO TOLSTOY - ANNA KORNINA, KREUTZER SONATA

HANS CHRISTIAN ANDERSON

WANG TAO - CHINESE SELF-STRENGTHENING MOVEMENT

AMEER MINAI - INDIAN SONG WRITER - AAHISTAA

MARRIAGESBARTHOLOMEW HEIFNER AND POLLY GRISHAM.IN SHELBY COUNTY, ENGLAND

Chapter 1 7

Wang Tao

Attempted to bring China into the 19th Century

Was put to death

Chapter 1 8

IMPORTANT EVENTSANDREW JACKSON ELECTED PRESIDENT OF USA DEFEATED JOHN Q. ADAMS

RUSSO-PERSIAN WAR ENDED

FATH ‘ALI SHAH’ AND RUSSIAN COUNTERPARTSIGNED TURKMANCHAI TREATY

GAVE RUSSIA - GEORGIA, ARMENIA, AND AZERBAIJAN

Chapter 1 9

Post 1828•Over 18,000 million compounds have been synthesized

•Pharmaceuticals

•Biochemicals

•Plastics

•Agrichemicals

•Paints

Chapter 1 10

Why so many organic?

H O N X P S Se

FORMS COVALENT BONDS WITH MANY METALS

Li Mg Al Cd Fe

FORMS COVALENT BONDS WITH NON-METALS

Chapter 1 11

WITH ITSELFC

CC

CC

CHAINS

CCH

CCH

C

CHAINS WITH BRANCHES

C CC

CC

C

CC

RINGS

No limit

AND

Chapter 1 12

Atomic Structure

• protons, neutrons, and electrons• isotopes

C12

6 6C14

=>

Chapter 1 13

Multiple Bonding

=>

Naming Hydrocarbons (nomenclature)

Drawing Structures: It’s All Good

CH3CH

CH

CH3

CH3CH3

CH3CH

CHCH3

2-butene

This is called the “condensed structure”

C C C C

H

H

H

H H H

H

H

CH3 CH CH CH3

On a test, choose a method that shows all HsCH3CH=CHCH3

Using brackets can also shorten some formulas: CH3CH2CH2CH2CH2CH3 vs. CH3(CH2)4CH3

Basic Naming of HydrocarbonsHydrocarbon names are based on: 1) type,

2) # of carbons, 3) side chain type and position 1) name will end in -ane, -ene, or -yne2) the number of carbons is given by a “prefix”

1 meth- 2 eth- 3 prop- 4 but- 5 pent- 6 hex- 7 hept- 8 oct- 9 non- 10 dec-

Actually, all end in a, but a is dropped when next to a vowel. E.g. a 6 C alkene is hexene

Q - What names would be given to these:7C, 9C alkane2C, 4C alkyne1C, 3C alkene

heptane, nonaneethyne, butynemethene, propene

Mnemonic for First Four Prefixes

First four prefixes• Meth-• Eth-• Prop-• But-

MonkeysEatPeeledBananas

?DecadeDecimal

Decathalon

Other Prefixes

• Pent-• Oct-• Dec-• Hex-, Hept-, Non-

Numbering CarbonsQ- draw penteneA- Where’s the double

bond? We # C atoms.

• Naming compounds with multiple bonds is more complex than previously indicated.

• When 2+ possibilities exist, #s are needed.• Always give double bond the lowest number.• Q - Name these

C C C CCH3

H

H

H

H H H

HCH31

C2

C3

C4

C5

H

H

H

H H H

HCH35

C4

C3

C2

C1

H

H

H

H H H

H

ethene3-nonyne

2-buteneCH3

CH

CH

CH3

CH3 CH3

C2H4

1-pentene

Formal Charge

• Formal charge: The charge on an atom in a molecule or a polyatomic ion.• To derive formal charge

1. Write a correct Lewis structure for the molecule or ion.2. Assign each atom all its unshared (nonbonding) electrons and one-half its shared

(bonding) electrons.3. Compare this number with the number of valence electrons in the neutral,

unbonded atom.

4. The sum of all formal charges is equal to the total charge on the molecule or ion.

Formal Charge

• Example: Draw Lewis structures, and show which atom in each bears the formal charge.

Apparent Exceptions to the Octet Rule

• Molecules that contain atoms of Group 3A elements, particularly boron and aluminum.

Apparent Exceptions to the Octet Rule• Atoms of third-period elements are often drawn with

more bonds than allowed by the octet rule.• The P in trimethylphosphine obeys the octet rule by

having three bonds and one unshared pair.• A common depiction of phosphoric acid, however, has

five bonds to P, which is explained by invoking the use of 3d orbitals to accommodate the additional bonds.

Apparent Exceptions to the Octet Rule

• However, the use of 3d orbitals for bonding is in debate. • An alternative representation that gives P in phosphoric

acid an octet has four bonds and a positive formal charge on P. The oxygen involved in the double bond of the alternative depiction has one bond and a negative formal charge.

Apparent Exceptions to the Octet Rule

• Sulfur is commonly depicted with varying numbers of bonds. In each of the alternative structures, sulfur obeys the octet rule.

Chapter 1 Bonding and Geometry

Chem 30ALecture 2

Functional Groups

• Functional group: An atom or group of atoms within a molecule that shows a characteristic set of physical and chemical properties.

• Functional groups are important for three reasons: 1. Allow us to divide compounds into classes.2. Each group undergoes characteristic chemical

reactions.3. Provide the basis for naming compounds.

Alcohols

• Contain an -OH (hydroxyl) group bonded to a tetrahedral carbon atom.

• Ethanol may also be written as a condensed structural formula.

Alcohols

• Alcohols are classified as primary (1°), secondary (2°), or tertiary (3°) depending on the number of carbon atoms bonded to the carbon bearing the -OH group.

Alcohols

There are two alcohols with molecular formula C3H8O

Amines

• Contain an amino group; an sp3-hybridized nitrogen bonded to one, two, or three carbon atoms.– An amine may by 1°, 2°, or 3°.

Aldehydes and Ketones

• Contain a carbonyl (C=O) group.

Carboxylic Acids

• Contain a carboxyl (-COOH) group.

Carboxylic Esters

• Ester: A derivative of a carboxylic acid in which the carboxyl hydrogen is replaced by a carbon group.

Carboxylic Amide• Carboxylic amide, commonly referred to as an amide: A

derivative of a carboxylic acid in which the -OH of the -COOH group is replaced by an amine.

– The six atoms of the amide functional group lie in a plane with bond angles of approximately 120°.