organic mechanisms

chlorination of alkanes conditions and equations

UV light

Cl-Cl -> .Cl + .Cl

.Cl + H-CH₃ ------> Cl-H + .CH₃

.CH₃ + Cl - Cl -------> CH₃Cl + .Cl

• .Cl + .CH₃ ------> CH₃Cl

• .Cl + .Cl -----> Cl₂

• .CH₃ + .CH₃ -----> C₂H₆

what reactions do halogenoalkanes undergo

nucleophilic substitution

elimination

nucleophilic substitutions of halogenoalkanes with :OH-

potassium/sodium hydroxide

warm and aqueous

nucleophilic substitutions of halogenoalkanes with :CN-

aqueous, ethanolic and warm

potassium cyanide

nucleophilic substitutions of halogenoalkanes with :NH₃

excess concentrated ammonia dissolved in ethanol at pressure in a sealed container

need two ammonias per reaction to make an ammonium halide as well as amine

elimination of halogenoalkanes with :OH-

hot and ethanolic

potassium/sodium hydroxide

what reactions do alkenes undergo

electrophilic addition

electrophilic addition of alkenes with hydrogen halides

make sure to think about

• Major product formed via more stable carbocation

• State which one is the more stable and that the major came from that

• Due to positive inductive effect of three alkyl/two alkyl groups rather than one

electrophilic addition of alkenes with halogens

aqueous

electrophilic addition of alkenes with concentrated sulfuric acid

must be concentrated and cold

electrophilic addition of alkenes with water

steam with strong sulfuric/phosphoric acid catalyst

300*C and 70atm

alcohol formed

what reactions do alcohols undergo

oxidation and elimination

how is ethanol formed from ethene

70atm

phosphoric acid catalyst

300*C

ethanol from fermentation

35*C, anaerobic, yeast

ethene from ethanol = elimination

hot

conc sulfuric acid

180*C

oxidation

acidified potassium dichromate (VI)

with sulfuric acid catalyst

heat to boiling point to go to aldehyde and immediately distil off

reflex - heating to boiling point for prolonged period of time for carboxylic acid

also Tollens and Fehlings are oxidation

Tollens - silver mirror formed on warming with aldehyde

Fehlings - on warming with aldehyde, blue solution to brick-red precipitate

what reactions do aldehydes and ketones

nucleophilic addition and reduction

reduction of aldehydes and ketones equation

nucleophilic addition of aldehydes and ketones

aqueous with NaBH₄

nucleophilic addition of aldehydes and ketones

sodium/potassium cyanide and dilute hydrochloric acid

aqueous

produce hydroxynitriles

what reactions do carboxylic acids and derivatives undergo

esterification and nucleophilic addition-elimination reactions

esterification

strong acid catalyst - sulfuric/hydrochloric

heat/warm

reversible reaction so hydrolysis in acidic conditions is the same

hydrolysis of esters

aqueous base (NaOH)

warm

alcohol and salt of acid produced

not reversible

biodiesel

nucleophilic addition-elimination reactions

products with acid anhydrides and acyl chlorides

with water and alcohol

no special conditions

with ammonia and amine

two molecules of ammonia/amine needed

what reactions do aromatics undergo

electrophilic substitutions

electrophilic substitution with nitronium ion

50*C, concentrated nitric and sulfuric acid

electrophilic substitution with acylium ion

acid anhydride/acyl chloride with AlCl₃

aluminium chloride is catalyst

anhydrous to prevent reaction of AlCl₃

mechanism with acid anhydride

what reactions make amines and what reactions can amines/ammonia do

nucleophilic substitution with halogenoalkanes

reduction of nitriles

reduction of nitro compounds

amines and ammonia can undergo nucleophilic substitution repeatedly with halogenoalkanes and nucleophilic addition-elimination reactions with acyl chlorides and acid anhydrides

nucleophilic substitution with halogenoalkanes

same as the above one from that topic

reduction with nitriles

first step is nucleophilic substitution of halogenoalkane with cyanide ion as above

then react with either:

LiAlH₄ in ethoxyethane or nickel catalyst, heat and H₂

reduction of nitro compounds

react with Sn and HCl, followed by NaOH