1 / 19

There are some questions in the middle part of the presentation so have a pen and paper ready.

Understand the mechanism of electrophilic addition reactions of alkenes using ethene and bromine as examples. Learn the role of electrophiles and carbocations in the process, along with the formation of saturated 1,2-dibromoethane. Questions presented for better comprehension.

ledward
Download Presentation

There are some questions in the middle part of the presentation so have a pen and paper ready.

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Electrophilic addition reactions of alkenes. There are some questions in the middle part of the presentation so have a pen and paper ready. There is some narration so turn the sound on!

  2. Electrophilic addition. Ethene and bromine liquid at room temperature.

  3. H H C C H Electrophile H Polarised Brδ+ Brδ-

  4. Carbocation H H H H C C C C + H H H H Brδ+ Br δ+ Brδ- Brδ- __ Curly arrows

  5. H H H H C H H C C H H C + + Br Brδ+ Brδ- __ Bromide ion Brδ- __

  6. H H Electrophilic addition C H H C Br Br Saturated 1,2-dibromoethane Unsaturated

  7. H H H H C C H H C H H C H H + Brδ+ Br C H H C Brδ- Brδ __ H H Br Br C H H C + Br Brδ __ Mechanism

  8. Write down the answers to the questions on a piece of paper. You will be given the answers in the final part of the presentation.

  9. Electrophilic addition. Ethene and bromine liquid at room temperature.

  10. H H C C H H Brδ+ Brδ-

  11. H H H H C C C C + H H H H Brδ+ Br δ+ Brδ- Brδ- __

  12. H H H H C H H C C H H C + + Br Brδ+ Brδ- __ Brδ- __

  13. H H C H H C Br Br

  14. Q1. From red-brown to colourless (not clear). Ethene and bromine liquid at room temperature.

  15. Q2. Ethene is unsaturated because it has a double bond between carbon atoms. H H C C H H Q3. The δ+ end of the Br2 acts as an electrophile Brδ+ Brδ-

  16. Q5. The carbon only has a single + charge because only one of the shared pair of electrons belonged to this carbon. H H H H C C C C + H H H H Brδ+ Br δ+ Brδ- Brδ- __ Q4. There is a single – charge because one of the shared pair of electrons already belonged to this bromine.

  17. Q6. A carbocation. H H H H C H H C C H H C + + Br Brδ+ Brδ- __ Q7. Curly arrows represent movement of a pair of electrons. Brδ- __

  18. H H Q8. The product is saturated. All the bonds between carbon atoms are saturated. C H H C Br Br Q9. 1,2-dibromoethane Q10. Electrophilic addition.

  19. Well done!

More Related