S–S Bond Activation in Multi‐Copper ­Aggregates Containing Perthiocarboxylato Ligands. Issue 24 (3rd August 2015)

• Record Type: Journal Article
• Authors: Troyano, Javier; Corral, Inés; Castillo, Oscar; Zamora, Félix; Mas‐Ballesté, Rubén; Delgado, Salomé
• Is Part Of: European journal of inorganic chemistry. Issue 24(2015)
• Page Start: 4044
• Page End: 4054
• Publication Date: 2015-08-03
• Subjects: Cluster compounds -- Copper -- Cuprophilia -- S ligands -- Density functional calculations; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201500494
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: The direct reaction between [Cu(OAc)2 · (H2 O)]2 and n ‐butyldithiocarboxylic acid affords two copper(I) aggregates with dithiocarboxylato, [Cu(S2 C‐ n ‐butyl)]4 (1 ), and perthiocarboxylato ligands, [Cu(S3 C‐ n ‐butyl)]4 (2 ), in which the oxidation of dithiocarboxylato ligand is triggered by the Cu II centers. The activation of the S–S bond in2 by two reducing agents, PPh3 and NaBH4, has been investigated both experimentally and by DFT calculations. The successive S–S activation in2 by reaction with 4 equiv. of PPh3 is a cooperative process, which implies that the intermediate species remain elusive. Such intermediates have been analyzed by DFT calculations, which established that the reactivity of the multi‐copper structures depends on the balance between the interactions in the different coordination spheres imposed on the copper centers and the Cu··· Cu distances. Furthermore, weak cuprophilic interactions are conditioned by the orbital orientation imposed by the structure. This implies that these metal–metal interactions are not always found between the pairs of Cu atoms with the shortest distances. Although different products have been isolated depending on the reducing agent, the overall theoretical data indicate that the reagent always attacks the terminal sulfur atom of the perthio group. Abstract : As a consequence of S–S activation in [Cu4 (μ‐S3 C‐ n ‐butyl)4 ], a complex reactivity is triggered in which both Cu–S coordination versatility and subtle Cu··· Cu interactions play distinct key roles.