For an example of the classical Gabriel synthesis of primary amines from an alkyl halide by alkylation of potassium phthalimide followed by hydrolysis, see: Org. Synth. Coll., 2, 25 (1943). For use of the Gabriel reaction on Merrifield resin as the first step of a synthesis of a polymer-supported carbodiimide, see: Org. Synth. Coll., 6, 951 (1988). The phthalimide alkylation is often carried out in DMF. A liquid-liquid phase-transfer method using (n-Hexadecyl)-tri-n-butyl-phosphonium bromide, as catalyst also gives excellent results: Synthesis, 389 (1976). The standard method for cleavage of the N-substituted phthalimide is with hydrazine hydrate, effective under milder conditions than acid or base hydrolysis. Other hydrazines and primary amines have also been successful, e.g. methylhydrazine or N,N-dimethylpropanediamine: Org. Synth. Coll., 9, 13, 16 (1998).
