1-Phenylethylamine

1-Phenylethylamine (1-PEA or α-PEA), also known as α-methylbenzylamine, is the organic compound with the formula C₆H₅CH(NH₂)CH₃. This primary amine is a colorless liquid is often used in chiral resolutions. Like benzylamine, it is relatively basic and forms stable ammonium salts and imines.

1-Phenylethylamine may be prepared by the reductive amination of acetophenone:

The Leuckart reaction, using ammonium formate, is another method for this transformation.

L-malic acid is used to resolve 1-Phenylethylamine, a versatile resolving agent in its own right. The dextrorotatory enantiomer crystallizes with the malate, leaving the levorotatory form in solution.

Similarly to benzylamine and analogues like pargyline, 1-phenylethylamine has been found to act as a monoamine oxidase inhibitor (MAOI), as well as an inhibitor of semicarbazide-sensitive amine oxidase (SSAO).