quick introduction to organic chemistry >> examville.com study guides

8/9/2019 Quick Introduction to Organic Chemistry >> Examville.com Study Guides

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ORGANIC CHEMISTRY

Organic chemistry is the study of ................containingcompounds derived from living organisms.

Oil is formed over millions of years from the break down ofdead ................and ......................

80+ millioncompounds- natural

& synthetic.

Crude Oil (petroleum) is a mixture of many thousands of thesedifferent compounds and is the main source of many of thesechemicals.

They are called .................. because they predominantly

contain the elements hydrogen and carbon.


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ORGANIC CHEMISTRY

Organic chemistry is the study of carbon containingcompounds derived from living organisms.

Oil is formed over millions of years from the break down ofdead creatures and plants.

80+ millioncompounds- natural

& synthetic.

Crude Oil (petroleum) is a mixture of many thousands of thesedifferent compounds and is the main source of many of thesechemicals.

They are called hydrocarbons because they predominantly

contain the elements hydrogen and carbon.


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DistillationofCrude Oil

Lower boiling point

substances ...............

and move up.

Asthe temp drops

substances ..............

and runoff.

..................temp

................... temp


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DistillationofCrude Oil

Lower boiling point

substancesvaporise

and move up.

Asthe temp drops

substancescondense

and runoff.

High temp

Lower temp


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Homologous series

This is a series of compounds which all contain the same

........................ group, and have similar chemicalproperties.

ALKANES ALKENES ALCOHOLS

CH4 CH2 =CH2 CH3OH

CH3-CH3 CH2=CH

CH3 CH3

CH2

OH

Each has a ...........................formula:

......................: CnH2n+2

The members of the series differ by the number of ......

units.CH3-CH3, CH3-CH2-CH3, CH3-CH2-CH2-CH3

Graduation in physical properties: eg: boiling points.

CH4 (......), C8H18 (..........), C30H62 (..............)


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ALKANESSATURATED HYDROCARBONS contain maximum amount of. - only .. bonds (no ..bonds)

NAMINGALKANES

NoofC atoms Prefix Formula Alkane

1 Meth CH4 Methane

2 Eth CH3CH3 Ethane

3 Prop CH3CH2CH3 Propane

4 But CH3CH2CH2CH3 Butane

5 Pent CH3CH2CH2CH2CH3 Pentane

6 Hex C6H14 Hexane

7 Hept C7H16 Heptane

8 Oct C8H18 octane


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ALKANESSATURATED HYDROCARBONS contain maximum

amount of hydrogen - only single bonds (no multiplebonds)

GENERAL FORMULACnH(2n+2)

NAMINGALKANES

NoofC

atoms

Prefix

1 Meth

2 Eth

3 Prop

4 But5 Pent

6 Hex

7 Hept

8 Oct

All alkanes endwith ANE.

All belong to the sameHOMOLOGOUS series


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Alkenes

Esters

Amines

(alcohol)~yl

(acid)~oate

Amino -

CH3CONH2

Acylchlorides

Amides

~oyl Chloride

~amide

Aldehydes

Carboxylic Acids

~al

~oic acid

CH3-IHaloalkanes

Ketones

Halo~

~one

CH2 = CH2

Alcohols

~ene

~olFunctional

groups

Thefunctionalgroups are

. or

..of atomswhichdeterminethe

.of organicmolecules.


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Alkenes

Esters

Amines

(alcohol)~yl

(acid)~oate

Amino -

CH3CONH2

Acylchlorides

Amides

~oyl Chloride

~amide

Aldehydes

Carboxylic Acids

~al

~oic acid

CH3-IHaloalkanes

Ketones

Halo~

~one

CH2 = CH2

Alcohols

~ene

~olFunctional

groups

Thefunctionalgroups are

atoms or

combinationsof atomswhichdetermine the

properties of

organicmolecules.


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STRUCTURES OF ALKANES

METHANE .

Bond

Angle .

Shape

Can be illustrated as:


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STRUCTURES OF ALKANES

METHANE CH4

Bond

Angle 109.5

o Shape

Tetrahedral

Can be illustrated as:

H

H C H

H

Methane isa

colourless

andouderless

flammeable

gas. Mr 12+4

= 16g.mol-1


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ETHANE.

Molecular formula ...

Structural formula:.. OR

.


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ETHANE.Molecular formula C2H6

Structural formula: CH3 CH3 or H H

H C C H

H H

Atomsare able tospinaround asingle

bond there isfree rotation.


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PROPANE.

Both ethane and propane are

chain moleculesBUT!! Bondsare 90o moleculesare NOT.!!!

Schematicformula

....................formula: C3H8

.....................formula: CH3 CH2 CH3 or H H H

H C C C H

H H H


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PROPANE.Molecular formula: C3H8

Structural formula: CH3 CH2 CH3 or H H H

H C C C H

H H H

Both ethane and propane arestraight chain molecules

BUT!! Bondsare NOT 90o moleculesare NOT STRAIGHT!!!

Straight = no branches!

Schematicformula

Ethane and propane are alsocolourlessand

odourlessflammable gasses. They have

slightly higher boiling points due totheir

greater molecularweights.


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ISOMERS

C4H10 - can have two different structures

Straight chain. CH3 CH2 CH2 CH3 BUTANE

Branched chain CH3 CH CH3

CH3 METHYL PROPANE

Compounds that have the same molecular formula but differentstructural formula are said to be ISOMERS of each other.

TASK: illustrate the structures of the three different isomers ofC5H12.

Use models ORCHEMSKETCH to help you.

branch


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Names & Structures

Examples2- methylbutane

CH3

CH3 CH CH2 CH3

CH3

CH3 C CH3

CH3

2,2 dimethyl propane

TASK: illustrate the structures of:

2-methylpentane.2,3 dimethylbutane.

2,2,3 -trimethylpentane

CH3CH(CH3)CH2CH2CH3

CH3CH(CH3)CH(CH3)CH3

CH3C(CH3)2CH(CH3)CH2CH3

The 2 can be left off as there are no other possibilities. 2 and3-methylbutane are the same molecule!

1 2 3 4


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THE RULES FOR NAMING ORGANICCOMPOUNDS

1. Choose the longest unbroken chain of Carbon atoms and assign a namefor the carbon chain using the prefixes; meth-1, eth-2 etc.

2. Identify any carbon chain branches (alkyl groups). These are assignednames using the same prefixes as above along with the suffix -yl methyl, ethyl etc.

3. Identify the functional groups present in the molecule. Assign a prefixor suffix according to their homologous series. These will be written in

front of the name of the carbon chain.

5. Number the Carbon atoms in the longest chain so that thebranches/functional groups have the lowest number possible. Allocate anumber for every group/branch no matter how many times it occurs.Where groups are on the same carbon write their names in alphabetical

order.6. Prefixes are used for groups that occur more than once.

Di 2 Tri 3 Tetra 4 Penta 5 etc.

7. Groups are written in alphabetical order.

8. The final name is written as one word with commas between numbers,hyphens separating numbers from words.


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Give the names of the following alkanes

(a)C

H3C

H2C

HC

H2C

H3CH3

(b) CH3 CH CH2 CH CH3

CH3 CH3

(c) CH3 C(CH3)2 CH2 CH(CH3) CH2 CH3

(d) CH3CH2CH(CH3)C(CH3)3


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Give the names of the following alkanes

3-methylpentane

2,4-dimethylpentane

2,2,4-trimethyl

hexane

(a)C

H3C

H2C

HC

H2C

H3CH3

(b) CH3 CH CH2 CH CH3

CH3 CH3

(c) CH3 C(CH3)2 CH2 CH(CH3) CH2 CH3

(d) CH3CH2CH(CH3)C(CH3)3 2,2,3-trimethylpentane


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The shape around the double bond is ...................

The bond angle around the double bond is .................

C CW bond4

4

.. ..

Represented as C C

Structure ofAlkenes


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The shape around the double bond is planer.

The bond angle around the double bond is 120o

C CW bond4

4

PLANER 120o

Represented as C C

Structure ofAlkenes


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ExamplesofAlkenes

, C2H4

H H

C C

H H

OR .

PROPENE CH2 CH CH3

TASK: Use ball & stick models or sketches to construct and name 3different structures for C4H8 each one with one double bond.


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ExamplesofAlkenes

ETHENE, C2H4

H H

C C

H H

OR CH2 CH2

PROPENE CH2 CH CH3

TASK: Use ball & stick models or sketches to construct and name 3different structures for C4H8 each one with one double bond.

CH3CH2CH CH2

CH3CH CHCH3

CH3C CH2

CH3

BUT-1-ENE

BUT-2-ENE

METHYLPROPENE

H H

C C

H CH3


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Alkynes

H-CC-H

H-CC-CH3

H-CC-CH2-CH3

CH3-CC-CH3

Ethyne

propyne

But1-yne

But2-yne

Very reactive

Triple bond unstable!

Attracts electrophiles.

C

x

xx

Alkynesare very ustable

and reactive. Acetylene

burnswithvery high

temp?


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