Synthesis of (3-(2-thiazolin-2-yl)thiazolidine-2-thione) (triphenylphosphine)-copper(I) bromide with a new coordination core of Cu(I)

The thio-ligand, 3-(2-thiazolin-2-yl)thiazolidine-2-thione (L², C₃H₄S₂N-C₃H₄SN), generated in situ from the reaction of thiazolidine-2-thione (L¹, NC₃H₅S₂) with copper(I) bromide in CH₃CN under aerobic conditions involved C–S bond cleavage and yielded a three coordinate complex, (3-(2-thiazolin-2-yl)thiazolidine-2-thione)copper(I) bromide 1. Treatment of 1 with PPh₃ in MeOH/CH₂Cl₂ mixture formed a copper(I) complex, (3-(2-thiazolin-2-yl)thiazolidine-2-thione)(triphenylphosphine)copper(I) bromide 2. This complex has four different types of donor atoms bonded to Cu(I) forming a central core,{Cu(N,P,S,Br)}, which is very unusual as normally the cores of known tetrahedral complexes are of type, {Cu(P₂,S,X)}(X = halogen).

Complex (3-(2-thiazolin-2-yl)thiazolidine-2-thione)(triphenylphosphine)copper(I) bromide 2 has unusual coordination core, Cu(N,P, S, Br).