A Zn3-bis(salphen) compound was used as a template for the construction of bidentate phosphine ligands by self-assembly with phosphines containing a carboxyl group. The convex shape of the template, exposing the three zinc atoms, ensured the correct orientation of the assembled diphosphine, such that it can coordinate to a single metal atom. The strong zinc-carboxylate bond guaranteed the integrity of the final assembly at the low concentrations (1 mM) used in catalysis. Depending on the substitution pattern of the benzoic acid phosphines, either monometallic chelates or dimeric complexes were formed. Coordination studies were carried out for Pt and Rh. A modest chelate effect in the rhodium catalyzed hydroformylation of 1-octene (l/b=4.7) confirmed the formation of the bidentate assemblies.