Abstract A series of novel (1-aminoalkyl)(trifluoromethyl)-and-(difluoromethyl) phosphinic acids–analogues of proteinogenic and nonproteinogenic α-amino acids were prepared. The synthetic methodology was based on nucleophilic addition of (trifluoromethyl) phosphinic acid or (difluoromethyl) phosphinic acid or its ethyl ester to substrates with C= N or activated C= C double bonds. Analogues of glycine, phenylglycine, alanine, valine, proline, ...