ocr organic reaction mechanisms n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
OCR organic reaction mechanisms PowerPoint Presentation
Download Presentation
OCR organic reaction mechanisms

Loading in 2 Seconds...

play fullscreen
1 / 15

OCR organic reaction mechanisms - PowerPoint PPT Presentation


  • 119 Views
  • Uploaded on

OCR organic reaction mechanisms. Click here for advice. Click a box below to go to the mechanism. AS. Free Radical Substitution. Electrophilic Addition. Nucleophilic Substitution. Electrophilic Substitution. A2. Nucleophilic Addition. Free radical substitution. chlorination of methane.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'OCR organic reaction mechanisms' - patty


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
ocr organic reaction mechanisms
OCR organic reaction mechanisms

Click here for advice

Click a box below to go to the mechanism

AS

Free Radical Substitution

Electrophilic Addition

Nucleophilic Substitution

Electrophilic Substitution

A2

Nucleophilic Addition

free radical substitution
Free radical substitution

chlorination of methane

i.e. homolytic breaking of covalent bonds

Overall reaction equation

CH4 + Cl2

CH3Cl + HCl

Conditions

ultra violet light

excess methane

to reduce further substitution

free radical substitution mechanism
Free radical substitution mechanism

Cl + Cl

CH4 + Cl

CH3 + HCl

CH3 + Cl2

CH3Cl + Cl

CH3 + Cl

CH3 + CH3

ultra-violet

Cl2

initiation step

two propagation steps

termination step

CH3Cl

minor termination step

CH3CH3

further free radical substitutions
Further free radical substitutions

Overall reaction equations

CH3Cl + Cl2

CH2Cl2 + HCl

CH2Cl2 + Cl2

CHCl3 + HCl

CHCl3 + Cl2

CCl4 + HCl

Conditions

ultra-violet light

excess chlorine

electrophilic addition
Electrophilic addition

bromine with ethene

Overall reaction equation

CH2=CH2

+ Br2

CH2BrCH2Br

1,2-dibromoethane

mechanism

bromine with ethene
bromine with ethene

H

H

C

C

H

H

H

H

C

C

H

H

+

Br

-

Br

Br

Br

+

Br

Br

H

H

-

C

C

H

H

Br

Br

Electrophilic addition mechanism

carbocation

1,2-dibromoethane

reaction equation

nucleophilic substitution
Nucleophilic substitution

water with bromoethane

mechanism

CH3CH2Br

+ H2O

CH3CH2OH + HBr

ethanol

hydroxide ion with bromoethane

mechanism

CH3CH2Br

+ OH-

(aqueous)

CH3CH2OH + Br-

ethanol

water with bromoethane
water with bromoethane

H

-

+

OH

C

CH3

H

+

H

O

H

C

H

CH3

Br

C

H

CH3

H

H

O

-

Br

H

H

H Br

Nucleophilic substitution mechanism

ethanol

reaction equation

hydroxide ion with bromoethane
hydroxide ion with bromoethane

H

-

+

OH

C

CH3

H

H

-

Br

Br

C

CH3

-

H

OH

Nucleophilic substitution mechanism

ethanol

reaction equation

electrophilic substitution
Electrophilic Substitution

Nitration of benzene

C6H6

+ HNO3

C6H5NO2

+ H2O

Conditions / Reagents

concentrated HNO3

and concentrated H2SO4

50oC

mechanism

electrophilic substitution mechanism nitration
electrophilic substitution mechanism (nitration)

NO2

+

1. Formation of NO2

H

+

+

NO2

O SO3H-

+

NO2

NO2

H O SO3H

the nitronium ion

HNO3

+ 2H2SO4

+ H3O+

+ 2HSO4-

2. Electrophilic attack on benzene

3. Forming the product

and re-forming the catalyst

reaction equation

nucleophilic addition
Nucleophilic Addition

HCN + OH-

addition of hydrogen cyanide to carbonyls to form hydroxynitriles

+ HCN

RCOR

RC(OH)(CN)R

RCH(OH)CN

+ HCN

RCHO

Conditions / Reagents

HCN (aq)

andNaOH(aq)

to form the CN- nucleophile

CN- + H2O

Room temperature and pressure

nucleophilic addition mechanism
Nucleophilic Addition Mechanism

C N

-

O

+

O

O

H

H CN

CN

C

CH3

C

CN

CH3

C

CN

CH3

CH3

CH3

CH3

CN

hydrogen cyanide with propanone

+ HCN

CH3COCH3

CH3C(OH)(CN)CH3

HCN / NaOH (aq) is a source of cyanide ions

2-hydroxy-2-methylpropanenitrile

advice
Advice

To get back to the mechanism links page from anywhere in the presentation, click the button at the top right corner of the screen.

This version provides the organic mechanisms specified (2002/3)

by the OCR exam board. Each stage of a reaction equation, its conditions and mechanism are revealed in turn on a mouse click or keyboard stroke. Note that there is another version available where each reaction and mechanism play automatically after an initiating click or key stroke.

The number of ways of navigating through this presentation may depend on the version of PowerPoint being used and how it is configured.

Some possible ways of advancing: left mouse click or return key or right arrow key or up arrow key.

Some possible ways of reversing: backspace key or left arrow key or down arrow key.

references
References

Steve Lewis for the Royal Society of Chemistry