Preparation of Organic Polysulfanes R2Sn (n = 5, 7, 8, 9) from Sulfenyl Chlorides, RSCl, and Transition Metal Polysulfido Complexes

Abstract

The preparation of seven novel organic polysulfanes is reported. Bis(n‐octyl)heptasulfane R2S7 1 is formed upon reaction of RSCl with [Cp2TiS5], while the corresponding nonasulfane R2S9 2 is obtained by reaction of RSSCl with [Cp2TiS5]. The bis(n‐octyl)pentasulfane R2S5 3 is obtained from RSCl and [(Cp′2TiCl)2S3] by transfer of the S3 ligand at 20 °C. The new alkyl polysulfanes 1–3 have been obtained in quantitative yields. They are liquids at 20 °C, having freezing points below –50 °C, but do not form mesogenic phases. Reactions of [Cp2TiS5] with 2‐naphthyl‐ and 4‐chlorophenyl sulfenyl chloride furnish the corresponding heptasulfanes 4 and 5, respectively, which are solids at 20 °C. 1,2‐Benzodisulfenyl chloride C6H4(SCl)2 reacts with [(Cp′2TiCl)2S3] to give the known 1,2,3,4,5‐benzopentathiepin C6H4S5 6, with [Cp2TiS5] to give the novel 1,2,3,4,5,6,7‐benzoheptathionin C6H4S7 7, and with [(TMEDA)ZnS6] to give the novel 1,2,3,4,5,6,7,8‐benzooctathiecin C6H4S8 8. The cyclic polysulfanes 6–8 are solids at 20 °C and have been recovered in yields of 60–83%. The orthorhombic structure of 1,2‐C6H4S7 has been investigated by single‐crystal X‐ray diffraction analysis. The molecules are found to be located at sites of Cs symmetry and the motif of the C2S7 heterocycle is +–+–+–+–, with the torsion angle of zero at the carbon–carbon bond. The three internuclear SS distances measure 205.0(1), 203.7(1), and 205.7(1) pm.

Polymerizations with elemental sulfur: A novel route to high sulfur content polymers for sustainability, energy and defense

“…To our knowledge, homocyclic polysulfides with between 16 and 19 sulfur atoms have not been prepared by the utilization of activated sulfur agents. However, the preparation of these species was presumably feasible given the development of suitable conditions for the use of sulfuryl dichloride and the appropriate metallocene Cp 2 TiS x (x= 3, 5, 7, 8) complex [121,122].…”

Benzo-Annelated Cyclic Polysulfides

“…The insertion of three sulfur atoms into 1,2bis(chlorosulfenyl)benzene (51a) proceeded on treatment with bis(bis(pentamethylcyclopentadienyl)chlorotitanium) trisulfide to give benzopentathiepin in good yield [35].…”

“…Steudel has reported benzo-annelated cyclic polysulfides with nine-membered, ten-membered and twelve-membered rings (Scheme 19) [35,37]. Titanocene polysulfide has been used as a sulfur transfer reagent, which reacted with 1,2bis(chlorosulfenyl)benzene (51) to produce the corresponding cyclic polysulfides (52), (53) and (54).…”

A New Route to Azadithiolato Complexes

“…Organotitanium complexes have proven to be versatile for the construction of unusual sulfur ligands. [8,9] For example, the (C 5 R 5 ) 2 Ti IV moiety has served as a platform for the novel sulfur-based ligands summarized in Scheme 1. [9] …”