Preparation and structures of tetrameric and dimeric manganese carbonyl complexes incorporating thiosalicylato ligands

Abstract

Orthomanganated N, N-dimethylbenzamide reacts with SO 2 to give a tetra-manganese complex Mn 4(thsa) 2(CO) 16 (thsa = thiosalicylate = 2-thiobenzoate di-anion) which an X-ray structure determination shows to contain four Mn(CO) 4 units linked by two triply bridging (S,O,O) thsa ligands. Another product identified after aerobic work-up was the disulphide [2-( −OOC)C 6H 4S-] 2. Reaction of thiosalicylic acid with BrMn(CO) 5 in the presence of Et 3N gave good yields of [Et 3NH] 2[Mn 2(thsa) 2(CO) 6], the anion of which contains two [Mn( η 2-thsa)(CO) 3] − units doubly-linked via the S atoms.