Sulfur Compounds, 212 Preparation of Organic Polysulfanes R_2S_n (n = 5, 7, 8, 9) from Sulfenyl Chlorides, RSCL, and Transition Metal Polysulfido Complexes

摘要

The preparation of seven novel organic polysulfanes is reported. Bis (n-octyl) heptasulfane R_2S_7 is formed upon reaction of RSCl with [Cp_2TiS_5], while the corresponding nonasulfane R_2S_9 2 is obtained by reaction of RSSCl with [Cp_2TiS_5]. The bis(n-octyl) pentasulfane R_2S_5 3 is obtained from RSCL and [(Cp'_2TiCl)_2S_3] by transfer of the S_3 ligand at 20 ℃. The new alkyl polysulfanes 1 - 3 have been obtained in quantitative yields. They are liquids at 20℃, having freezing points below -50 ℃, but do not form mesogenic phases. Reactions of [Cp_2TiS_5] with 2-naphtyl- and 4-chlorophenyl sulfenyl chloride furnish the corresponding heptasulfanes 4 and 5, respectively, which are solids at 20 ℃. 1,2-Benzodisulfenyl chloride C_6H_4(SCl)_2 reacts with [(Cp'_2TiCl)_2S_3] to give the known 1,2,3,4,5-benzopentathiepin C_6H_4S_5 6, with [Cp_2TiS_5] to give the novel 1,2,3,4,5,6,7-benzoheptathionin C_6H_4S_7 7, and with [(TMEDA) ZnS_6] to give the novel 1,2,3,4,5,6,7,8-benzooctathiecin C_6H_4S_8 8. The cyclic polysulfanes 6-8 are solids at 20 ℃ and have been recovered in yields of 60-83%. The orthorhombic structure of 1,2-C_6H_4S_7 has been investigated by single-crystal X-ray diffraction analysis. The molecules are found to be located at sites of C_s symmetry and the motif of the C_2S_7 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.