Potentially tridentate, phosphine-containing Schiff bases with P,N,O and P,N,P donor sets have been prepared from 2-(diphenylphosphino)benzaldehyde, salicylaldehyde, 2-aminophenol and 2-((diphenylphosphino)phenyl)methylamine and reacted with (NEt4)(2)[Re(CO)(3)Br-3] in methanol. Deprotonation and the formation of neutral [Re(CO)(3)(L)] complexes with tridentate coordination of the Schiff bases has been obtained for the salicylidene derivatives, while the potential P,N,P ligand L-3 forms [Re(CO)(3)Br(L-3)] with the Schiff base in a bidentate bonding mode. The formation of a cationic [Re(CO)(3)(L-3)](+) complex with tripodal coordination of the organic ligand could be achieved by the addition of Ag(PF6) to the reaction mixture. The obtained rhenium(I) complexes were studied spectroscopically and by X-ray diffraction