Versatility of Thiosemicarbazones in the Construction of Monomers, Dimers and Hydrogen-Bonded Networks of Silver(I) Complexes

Abstract

Reactions of thiosemicarbazones {R 1 R 2 C 2 dN 3 -N 2 (H)-C 1 (dS)-N 1 H 2 }, a multidonor class of ligands, with silver(I) halides in the presence of PPh 3 have yielded a variety of compounds, viz.: 6)), and (iii) monomers, [AgX(η 1 -S-Hpytsc)(PPh 3 ) 2 ] • CH 3 CN (R 1 ) pyridine, R 2 ) H, Hpytsc, X ) Br (7); Cl (8)). In contrast, silver(I) nitrate has formed only sulfur-bridged dimers, [Ag 2 (η 1 -N-µ-S-Hftsc) 2 (Ph 3 P) 2 ](NO 3 ) 2 (9) (R 1 ) furan, R 2 ) H, Hftsc), and [Ag 2 (η 1 -S-Hptsc) 2 (µ-S-Hptsc) 2 (Ph 3 P) 2 ](NO 3 ) 2 • 2CHCl 3 (10) (R 1 ) pyrrole, R 2 ) H, Hptsc) (Hpytsc ) pyridine-2-carbaldehyde thiosemicarbazone, Hptsc ) pyrrole-2-carbaldehyde thiosemicarbazone, Httsc ) thiophene-2-carbaldehyde thiosemicarbazone, Hftsc ) furan-2-carbaldehyde thiosemicarbazone, Hbtsc ) benzaldehyde thiosemicarbazone, Hactsc ) acetone thiosemicarbazone, and Haptsc ) acetophenone thiosemicarbazone). Complexes 1-10 are the first examples exhibiting new bonding modes (η 1 -S, µ-S, and µ-S-η 1 -N 3 ) in silver(I)thiosemicarbazone chemistry. The substituents at C 2 carbon appear to have significant influence on the nature of bonding in the complexes. The intermolecular interactions such as, NH • • • X (X ) S, Br, Cl, O), CH • • • π and CH • • • X (X ) S, Cl) have led to the formation of one-and two-dimensional (1D and 2D) networks. Interestingly, a novel feature is that some of the 2D networks encapsulate organic molecules in the voids.

Bonding and structure trends of thiosemicarbazone derivatives of metals—An overview

“…There are a few silver(I)-thiosemicarbazone complexes [308][309][310][311][312]. Thiosemicarbazones with silver(I) halides in presence of PPh 3 have yielded a variety of compounds, (Chart 46), (i) monomers, [AgX( 1 -S-HL)(PPh 3 ) 2 ]·CH 3 CN 381, 382 (Fig.…”

“…33, 384) and (iii) sulfur-bridged dimers, [Ag 2 Br 2 (-S-HL) 2 (PPh 3 ) 2 ]·2H 2 O 387 (Fig. 34), [Ag 2 Cl 2 (-S-HL) 2 (PPh 3 ) 2 ]·2CH 3 CN 388 [310]. Silver(I) nitrate forms sulfurbridged dimers, [Ag 2 ( 1 -N--S-HL) 2 (Ph 3 P) 2 ](NO 3 ) 2 389 (Fig.…”

“…Silver(I) nitrate forms sulfurbridged dimers, [Ag 2 ( 1 -N--S-HL) 2 (Ph 3 P) 2 ](NO 3 ) 2 389 (Fig. 35) , [Ag 2 ( 1 -S-HL) 2 (-S-HL) 2 (Ph 3 P) 2 ](NO 3 ) 2 ·2CHCl 3 390 [310] and a triply hetero-bridged [Ag(-P,P-dppm) 2 (-S-HL)Ag(ONO 2 )]NO 3 391 dimer (Fig. 36) with a short Ag· · ·Ag contact of 2.9939(7)Á [311].…”

Comparative Solution Equilibrium Study of the Interactions of Copper(II), Iron(II) and Zinc(II) with Triapine (3‐Aminopyridine‐2‐carbaldehyde Thiosemicarbazone) and Related Ligands

“…[15,16] Monodentate coordination through the thione group has also been documented in the case of soft-metal ions such as Ag I and Hg II . [17] When a coordinating functionality is additionally present in the TSC ligand, more diversified binding modes can occur; typically, tridentate (X,N,S) coordination can be found in the octahedral bis-ligand complexes, in which X is the donor atom of the additional functional group. Sulfur too can serve as a bridging ligand to an adjacent metal centre to form dimers (e.g., in the case of Cu II ).…”

Síntese e caracterização estrutural do ligante isatina-3-(N4-benziltiossemicarbazona) e do seu complexo de mercúrio(II)

“…O estudo de cadeias supramoleculares é importante no contexto de suas aplicações como carreadores no transporte de drogas em sistemas biológicos, bem como na detecção de traços de metais. 9,10 São descritas na literatura 7 a preparação, caracterização espectroscópica e termogravimétrica de complexos do ligante isatina-btiossemicarbazona com vários metais, entre eles o mercúrio (II). Desta forma, a elucidação estrutural das moléculas aqui apresentadas é uma contribuição relevante ao estudo da química das tiossemicarbazonas.…”