organic synthesis Flashcards
Carbon-carbon bond formation
Important as they provide a way of creating new compounds with more carbon atoms
Nitriles from haloalkanes
Formed by reacting haloalkanes with sodium cyanide (NaCN) or potassium cyanide in ethanol, in this reaction the length of the carbon chain increases. This is nucleophilic substitution. Possible reaction =CH3CH2Cl + KCN –> CH3CH2CN + KCl
Nitriles from aldehydes and ketones
Aldehydes and ketones will with react with HCN. However, HCN is too poisonous to use so instead a mixture of NaCN and sulfuric acid is used, to improve safety and reaction rate
CH3COCH3 + HCN –> CH3C(OH)(CN)CH3
Reduction of nitriles
Nitriles can be reduced to amines by reacting with hydrogen in the presence of a nickel catalyst
CH3CN + 2H2 –> CH3CH2NH2
Hydrolyses of nitriles
Nitriles undergo hydrolyses to form carboxylic acids by heating with dilute aqueous acid i.e. HCl
CH3CN + 2H2O + HCl –> CH3COOH + NH4Cl
Alkylation of benzene rings
Alkylation is a reaction which transfers an alkyl group from a haloalkane to a benzene ring. The catalyst AlCl3 is needed, HCl is also produced
Alcylation of benzene rings
When a benzene ring reacts with an alcyl chloride in the presence of an aluminium chloride catalyst, a ketone is formed. HCl is also produced
Nitriles to carboxylic acid
H2O, HCl, heat
Acyl chloride to carboxylic acid
H2O
Aldehyde/ketone to alcohol
NaBH4
Alcohol to alkene
H2SO4 and heat
Haloalkane to alcohol
NaOH (aq)
Aldehyde/ketone to hydroxynitrile
NaCN(aq)/H+(aq)
Haloalkane to amine
NH3 in ethanol
Alcohol to haloalkane
Sodium halide and H2SO4
Acyl chloride to secondary amide
Primary amine
Acyl chloride to primary amide
NH3
Alkene to alcohol
H2O (steam) / H3PO4
Ester to carboxylate salt
Hot aqueous alkali
Alkene to alkane
H2/Ni 150 degreese
Ester to carboxylic acid
Hot aqueous acid
Carboxylic acid to ester
Alcohol / conc. H2SO4
Nitrile to amine
H2 / Ni
Haloalkane to nitrile
NaCN or KCN in ethanol
Alcohol to aldehyde
K2Cr2O7 / HSSO4 distil
Alcohol to ester
Carboxylic acid / conc. H2SO4 or acid anhydride or acyl chloride
Alcohol to carboxylic acid
K2Cr2O7 / H2SO4, reflux
Alkane to haloalkane
Halogen, UV
Acyl chloride to ester
Alcohol
Carboxylic acid to acyl chloride
SOCl2
Alkene to haloalkane
Hydrogen halide
How do you prepare a solid substance to be tested
Dissolve 5 grams of the substance in the minimum amount of hot water whilst stirring. Then filter it to remove the debris
