Unit 2-Alkenes Flashcards
State methods of preparing alkenes.
Dehydration of an alcohol acid dehydration
Elimination of hydrogen halide from monohaloalkanes
Draw the mechanism for acid hydration of an alcohol.
What is the elimination of hydrogen halide from monohaloalkanes catalysed by?
a base
State 5 reactions of alkenes.
All ELECTROPHILIC ADDITION:
Catalytic addition of hydrogen to form alkanes
Reaction with hydrogen halides
Reaction with water to form alcohols
Addition of halogens to alkenes
What kinds of reactions do alkenes usually undergo?
Electrophilic Addition reactions
Why do alkenes behave as nucleophiles?
They contain carbon to carbon double bonds which is a region of high electron density
When alkenes reaction with hydrogen halides what do they produce?
monohaloalkanes
What is Markovnikov’s rule?
In the addition of H-X to an alkene, the H atom attaches to the carbon atom of the alkene which already has more hydrogen atoms
What does electrophilic addition of water to an alkene produce?
an alcohol
What does electrophilic addition of water to an alkene require?
an acid catalyst
For the acid catalysed addition of water, what does the water act as?
Nucleophile
What kind of intermediate does the addition of a bromine molecule to ethene form?
cyclic intermediate
What is the mechanism for adding a halogen to an alkene?
What is the mechanism for adding a hydrogen halide to an alkene?
