Organic chemistry
Sponsored Links
This presentation is the property of its rightful owner.
1 / 13

ORGANIC CHEMISTRY PowerPoint PPT Presentation


  • 75 Views
  • Uploaded on
  • Presentation posted in: General

ORGANIC CHEMISTRY. HYDROCARBONS. H H C C H H. OR CH 2 CH 2. H H C C H CH 3. PROPENE CH 2 CH CH 3. CH 3 C CH 2 CH 3. CH 3 CH CHCH 3. CH 3 CH 2 CH CH 2. Examples of Alkenes. ETHENE, C 2 H 4.

Download Presentation

ORGANIC CHEMISTRY

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


ORGANIC CHEMISTRY

HYDROCARBONS


H H

C C

H H

OR CH2 CH2

H H

C C

H CH3

PROPENE CH2CH CH3

CH3C CH2

CH3

CH3CH CHCH3

CH3CH2CHCH2

Examples of Alkenes

ETHENE, C2H4

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

BUT-1-ENE

2METHYL PROP 1 ENE

BUT-2-ENE


CH2 CHCH2CH2CH3

CH3CH2CH CHCH2CH3

CH2 C(CH3)CH2CH3

CH3CHCHCH2CH3

CH2 CHCH(CH3)CH2CH3

CH3CH(CH3)CH CHCH2CH3

(CH3)3CCH C(CH3)2

More Alkenes

Illustrate structures of the following alkenes:

Pent-1-ene

Hex-3-ene

2-methylbut-1-ene

Cyclohexene

Name the following alkenes

Pent-2-ene

3-methylpent-1-ene

2-methylhex-3-ene

2,4,4-trimethylpent-2-ene


Alkynes

H-C≡C-H

Ethyne

Very reactive

Triple bond unstable!

Attracts electrophiles.

H-C≡C-CH3

propyne

H-C≡C-CH2-CH3

But–1-yne

But–2-yne

CH3-C≡C-CH3


Naming Aromatics

  • Same rules

  • If benzene is the parent chain “benzene” suffix

  • If benzene is a branch group “phenyl”


Structural Isomers

  • Structural isomers are compounds with the same molecular formula but different structural arrangements

  • They will have different physical and chemical properties

  • Example:

    • pentane

    • 2-methylbutane

    • 2,2-dimathylpropane


Cis-Trans Isomers

  • Cis-trans isomersoccur when different groups of atoms are arranged around a double bond

  • Unlike a single C-C bond that can rotate, the double C=C bond is fixed

Opposite side

Same side

cis-1,2-dichloroethene

trans-1,2-dichloroethene


BUT–2-ENE CH3 CH CH CH3

CH3 CH3

C C

H H

CH3 H

C C

H CH3

GEOMETRIC ISOMERS

  • There is no rotation about the doublebond.

GEOMETRIC ISOMERISM each C atom in the doublebond has two differentatoms/groups attached.

trans but-2-ene

cis but-2-ene

Geometric isomerism is a form of STEREOISOMERISM –

Same molecular and structural formula but atoms are arranged differently in space


All Hydrocarbons will Undergo Combustion:Complete:CH4 + 2O2 CO2 + 2H2OIncomplete:CH4 + O2 CO2 + CO + C + H2O


Alkanes & Aromatics Undergo Substitution Reactions

  • One or more of the hydrogen atoms can be replaced by a halogen

  • You can then add other functional groups by replacing the halogen

  • Requires heat, UV light or a catalyst (not easily done with alkanes! But is easier with aromatics)

  • Alkane + halogen → hydrogen halide + alkyl halide


Alkenes & Alkynes Undergo AdditionReactions:· Much greater chemical reactivity than alkanes· Easily undergo addition reactions at room temperature (calledaddition reaction b/c there is no loss of hydrogen atom(s))


Addition Reactions

  • ReactantsProductDescriptive Name

  • \ / | |

  • C = C + HX → - C – C - Hydrohalogenation

  • / \ | | (X = Br, F, I, Cl…)

  • X


Markovnikov’s Rule:When a hydrogen halide (e.g. HBr) or water (HOH) is added to an alkene the hydrogen atom will bond to the carbon atom within the multiple bond that already had more hydrogen atoms.CH3-CH2-CH=CH2 + HCl -------------------------> CH3-CH2-CH(Cl)-CH3 This rule doesn't apply for the addition of symmetrical reagents like Br2 or Cl2


  • Login