Stepwise Synthesis and Crystal Structure of Tricarbonyl[pentakis(methylthio)cyclopentadienyl]-manganese [{C5(SMe)5}Mn(CO)3]

Isolation and crystal and molecular structures of [(C5H2Br3)2Fe], [(C5HBr4)2Fe] and [(C5Br5)(C5Br4HgBr)Fe]

The reaction of [(C5H3Br2)2Fe] with lithium tetramethylpiperidinide (LiTMP) in a 1:10 molar ratio in tetrahydrofuran yields, after quenching with C2H2Br4, a mixture of the polybromoferrocenes [C10H10-nBrnFe] with n = 4-9, from which single crystals of bis(1,2,3-tribromocyclopentadienyl)iron(II), [Fe(C5H2Br3)2], and bis(1,2,3,4-tetrabromocyclopentadienyl)iron(II), [Fe(C5HBr4)2Fe], were obtained by a combination of chromatography and fractional crystallization. Treatment of `[C10(HgOAc)10Fe]' with KBr3 yields a mixture of polybromoferrocenes [C10H10-nBrnFe] with n = 8-10 and bromomercurioferrocenes [C10H9-nBrn(HgBr)Fe] with n = 7-9, from which single crystals of (1-bromomercurio-2,3,4,5-tetrabromocyclopentadienyl)(1,2,3,4,5-pentabromocyclopentadienyl)iron(II), [FeHgBr(C5Br4)(C5Br5)], were obtained by fractional crystallization. The crystal structures of all the compounds show Br...Br, Br...H and sometimes Br...Cp...π (Cp is a ring centroid) interactions, as well as π-π interactions. The findings are supported by Hirshfeld analyses.

Ferrocenes with a Persulfurated Cyclopentadienyl Ring: Synthesis, Structural Studies, and Optoelectronic Properties

Persulfurated arenes are a fascinating class of functional molecules with a wide range of potential applications. Ferrocenes are also a multifaceted class of aromatic compounds that can easily be finetuned for an enormous variety of desired properties. A combination of both substance classes might yield an even wider field of applications. Herein, we describe the synthesis of two ferrocenes with one persulfurated cyclopentadienyl ring [C₅ (SR)₅ ], with R=Me or Ph, together with their crystal structures, optical, and electrochemical properties. Both crystal structures show significant intramolecular sulfur-iron interactions as well as weak intermolecular sulfur- contacts. Cyclovoltammetry of the [C₅ (SPh)₅ ] compound shows a high oxidation potential of 651 mV vs. FcH/FcH⁺ .

Persulfurated Aromatic Compounds

Persulfurated arenes have been known for about 50 years but they were underexploited in chemistry in spite of facile, mild, and high-yielding syntheses. Their properties (redox potentials, UV/Vis absorption, conductivity, nonlinear optical properties, etc.) are mainly due to the aromaticity of the ring with sp2-hybridized carbon atoms and to the electronic contribution from numerous divalent sulfur ligands, which also stabilize negative or positive charges. The characteristic conformational patterns of the sulfur ligands often facilitate preorganization in supramolecular assemblies, with or without thiophilic metal cations, for designing redox sensors, ion-selective membranes, clathrates, organic conductors, nonlinear optical materials, liquid crystals, coordination polymers, and bioinorganic systems. A new class of supramolecules with various molecular shapes such as asterisks, chains, wheels, and windmills were reported.