Chemical Reactions
Chapter Name : Haloalkanes And Haloarenes |
Sub Topic Code : 102_12_10_06_04 |
Topic Name : Chemical Reactions |
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Sub Topic Name : Reaction With Metals |
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Introduction
• Most organic chlorides, bromides and iodides react with certain metals to give compounds containing carbon-metal bonds. • Such compounds are known as organo-metallic compounds • An important class of organo-metallic compounds discovered by Victor Grignard in 1900 is alkyl magnesium halide, RMgX, referred as Grignard Reagents. • Grignard reagents are highly reactive and react with any source of proton to give hydrocarbons. • Even water, alcohols, amines are sufficiently acidic to convert them to corresponding hydrocarbons. • It is therefore necessary to avoid even traces of moisture from a Grignard reagent. • On the other hand, this could be considered as one of the methods for converting halides to hydrocarbons. • Alkyl halides react with sodium in dry ether to give hydrocarbons containing double the number of carbon atoms present in the halide. • This reaction is known as Wurtz reaction.
Pre-Requisites:
Elements, bond, halides
Activity:
• Synthetic halogen compounds, viz. • chloroquine is used for the treatment of malaria; • Halothane is used as an anaesthetic during surgery.
Real Life Question:
What are haloarenes and haloalkanes?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| - Haloalkanes - Haloarenes | • Haloalkanes contain halogen atom(s) attached to the sp3 hybridised carbon atom of an alkyl group. • Haloarenes contain halogen atom(s) attached to sp2 hybridised carbon atom(s) of an aryl group. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| • Chlorine containing antibiotic, chloramphenicol, produced by soil microorganisms is very effective for the treatment of typhoid fever. |
Real life uses :
• Synthetic halogen compounds, viz. ? chloroquine is used for the treatment of malaria; ? .Halothane is used as an anesthetic during surgery..
Places to visit :
Pharmacy.
Practical examples around us
| Examples | Explainations |
|---|---|
| • Synthetic halogen compounds, viz. ? chloroquine is used for the treatment of malaria; ? Halothane is used as an anesthetic during surgery. |
What you learn in Theory:
• Most organic chlorides, bromides and iodides react with certain metals to give compounds containing carbon-metal bonds. • Such compounds are known as organo-metallic compounds • An important class of organo-metallic compounds discovered by Victor Grignard in 1900 is alkyl magnesium halide, RMgX, referred as Grignard Reagents. • Grignard reagents are highly reactive and react with any source of proton to give hydrocarbons. • Even water, alcohols, amines are sufficiently acidic to convert them to corresponding hydrocarbons. • It is therefore necessary to avoid even traces of moisture from a Grignard reagent. • On the other hand, this could be considered as one of the methods for converting halides to hydrocarbons. • Alkyl halides react with sodium in dry ether to give hydrocarbons containing double the number of carbon atoms present in the halide. • This reaction is known as Wurtz reaction.
What you learn in Practice:
• Haloalkanes and Haloarenes are classified based on the number of halogen compounds contained in them.