carboxylic acids and derivatives Flashcards
oxidation of aldehyde to produce a carboxylic acid
h2so4 and k2cr2o7
heat under reflux
CH3CHO + [O] —> CH3COOH
full oxidation of a primary alcohol to produce a carboxylic acid
h2so4 and k2cr2o7
heat under reflux
CH3CH2OH + 2[O] —> CH3COOH + H2O
hydrolysis of a nitrile to produce a carboxylic acid
dilute HCL
heat under reflux
CH3CN + 2H2O + HCl —> CH3COOH + NH4Cl
hydrolysis of an amide
HCl catalyst
water
produces carboxylic acid and ammonia
gringard reagent to produce a carboxylic acid
gringard reagent + CO2
dilute HCl catalyst
CH3CH2MgI + CO2 —> CH3CH2COOH + Mg(OH)I
test for carboxylic acid with a carbonate
add a small quantity of carbonate to sample
collect gas into a test pipette and bubble through a small volume of fresh lime water
gas evolved turns limewater cloudy
carboxylic acid + metal
salt + hydrogen
carboxylic acid + alkali
salt + water
carboxylic acid + carbonate
salt + water + carbon dioxide
why are carboxylic acids acidic but alcohols (that also contain OH) are not
when a proton is lost a pi bond is formed over the COO- group
the negative charge is delocalised between the 3 atoms
this stabilises the carboxylate ion
alcohols do not have this delocalisation so do not readily lose a proton
reducing carboxylic acids (to 1° alcohol)
LiAlH4
in dry ether
warm with dilute HCl (hydrolysis)
CH3COOH + 4[H] —> CH3CH2OH + H2O
test for a carboxylic acid with sulphuric acid, ethanol and Na2CO3
add 1cm3 ethanol
2 drops conc sulphuric acid
warm in water bath
tip onto saturated solution of Na2CO3
smell cautiously
formation of an acyl chloride
add PCl5 to a carboxylic acid
anhydrous conditions
—> R-COCl + POCl3 + HCl
what are carboxylic acids reduced to
alcohols
reduction of COOHs
LiAlH4
solution of dry ether
warming with dilute HCl