Abstract In order to obtain soluble complexes containing sterically protected metal centers the new bi- and tetradentate thiolate amine ligands 2-mercapto-3,5-di-tbutylaniline (= tbu2-ma-H) and 1,2-bis(2-mercapto-3,5-di-tbutylanilino)ethane (= tbu4-mae-H2) were synthesized. tbu2-ma-H reacts with FeCl2-4 H2O and CO to give [Fe(CO)2(tbu2-ma)2], with Zn(ac)2 -2 H2O [Zn(tbu2-ma)2] is obtained whose acid hydrolysis and reaction with H2S, respectively, yield pure tbu2-Ina-H. The condensation of tbu2-ma-H with glyoxal yields the respective bis-benzthiazolidine, which is reduced by LiAlH4 in the presence of Na[N(SiMe3)2] to tbu4-bmae-H2. tbu4-bmae-Li2. reacts with [Ru(CO)3(THF)Cl2], [Ru(PMe3)4Cl2] and [Ru(PPh3)2(CH3CN)2Cl2], respectively, to yield [Ru(L)2(Tm4-bmae)j (L = CO, PMe3, PPh3). The complexes are more soluble in organic solvents than the corresponding unsubstituted bmae complexes, bmae2- = 1,2-bis(2-mercaptoanilino)- ethane(2-).