Submitted to: Inorganica Chimica Acta
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/13/2008
Publication Date: 3/2/2009
Citation: Benny, P.D., Fugate, G.A., Morley, J.E., Twamley, B., Trabue, S.L. 2009. Synthesis and characterization of 5-bis(benzyl thio)-1, 3, 4-thiadiazole complexes with fac-ReBr3(CO) 32-. Inorganica Chimica Acta. 362:1289-1294. Interpretive Summary: The construction of coordination polymers and supramolecular complexes is of interest due to the many applications they have in catalysis, pharmaceuticals, and photochemical materials through their ability to form associations with metals through linkages with sulfur and nitrogen compounds in the molecule. This paper investigates the interactions of 2,5-bis(benzylthio)-1,3,4-thiadiazole (Compound 1) with fac-ReBr3(CO)32 by measuring the absorbance and emission capabilities of these complexes. Reactions of Compound 1 with the rhenium starting material yielded two distinct types of complexes which were coordinated through the nitrogen-containing thiadiazole ring only. No evidence was suggested that the ligand would coordinate through either of the thioether donors in Compound 1. The information presented in this paper is intended to be used by researchers in radiopharmaceuticals, bioinorganic, and material science.
Technical Abstract: Reactions of 2,5-bis(benzylthio)-1,3,4-thiadiazole (Compound 1) with a common organometallic rhenium starting material [NEt4]2[fac-[Re(I)Br3(CO)3] yielded two distinct types of complexes. Both complexes coordinate only through the nitrogen of the thiadiazole ring. Reaction of Compound 1 with the rhenium starting material alone yielded a bimetallic complex fac-(di-mu-bromo) (mu-2,5-bis(benzylthio)-1,3,4-thiadiazole-kappaN:'kappa’N) bis (tricarbonyl rhenium (I)) (Compound 2). The nitrogens of the thiadiazole ring of Compound 1 each coordinate to a different rhenium center combined with two bridging bromide ligands in Compound 2. Compound 2 crystallized in a monoclinic system, P2(1)/n space group with a= 13.8647(17) Å, b=12.7260(16) Å, c= 15.3535(19) Å, beta = 98.582(2) ° V= 2678.7(6) Å3 and Z= 4. A “2+1” complex was prepared in a two-step process by reacting the rhenium starting material with picolinic acid followed by Compound 1 to yield fac-Re(I)(2,5-bis(benzylthio)-1,3,4-thiadiazole)(CO)3(picolinate) (Compound 3). Compound 3 crystallized in a triclinic system, P-1 space group with a= 12.282(4) Å, b= 14.072(4) Å, c= 15.554(4) Å, alpha = 101.381(4)°, beta = 104.464(4)°, gamma = '91.371(4)°, V= 2544.2(13) Å3 and Z= 2.