Chromium(III) complexes containing N,N′-ethylene-bis(salicylideneiminate) as a ligand

Abstract Numerous six-coordinate chromium(III) complexes with N,N′-ethylene-bis(salicylideneiminate) (abbreviated as Salen) have been synthesized. The complexes obtained are [Cr(Salen)L 2 ]X. nH 2 O (X=Cl or NCS; L=H 2 O, NH 3 , CH 3 NH 2 , C 2 H 5 NH 2 , n-C 3 H 7 NH 2 , n-C 4 H 9 NH 2 , and pyridine), K[Cr(CN) 2 Salen)], [CR(ONO)Salen(H 2 O)], [CrCl(Salen)py], and [Cr(Salen)(H 2 O)py]Cl. The complexes of the type [Cr(Salen)(H 2 O) 2 ]X have been obtained by a reaction of chromium(III) chloride hexahydrate with N,N′-ethylene-bis(salicylideneimine) in ethylene glycol-water-methanol at about 120° , by a reaction of NH 4 [Cr(NCS) 4 (NH 3 ) 2 ]. H 2 O with N,N′-ethylene-bis(salicylidenimine) in methanol, and by Collman's modified method using anhydrous chromium(III) chloride in tetrahydrofuran. The other complexes have been derived from [Cr(Salen)(H 2 O) 2 ]X. The nitrite ion in [Cr(ONO)Salen(H 2 O)] is bound with the chromium(III) ion through the oxygen atom.