Gabriel’s Phthalimide Synthesis

--Abuturab mohammadi

Gabriel’s phthalimide systhesis converts R-X and NH3 into 1˚amine

First step is the conversion of phthalic anhydride into phthalamide

Phthalic acid is reused as anhydride and thus is the carrier of the reaction[DMF is polar aprotic solvent and is an excellent medium for SN2]

The alkyl halide undergoes nucleophilic displacement by phthalimide anion(sn2)to form N-substituted phthalimide the latter is then hydrolysed either by acid or by alkali

Instead of using acid or base hydrolysis hydrazine can also be used if hydrolysis is difficult

Gabriel’s sysnthesis is useful for the synthesis of complex compund because phthalimide group is fairly unreactive & is easily separated at the end of hydrolysis

It is the best method of preparation of 1˚amines