Sodium disulfide and monosulfide were selectively formed via the direct reaction of sulfur and an equimolar amount of sodium in 1,2-dimethoxyethane at 70 degrees C in the presence of a catalytic amount of aromatic hydrocarbons and ketone.

The directed synthesis of main chain-type polyrotaxanes possessing crown ether wheels was successfully achieved through two methods, A and B. Method A involved the direct wheel threading of poly(sec-ammonium salt) followed by end-capping with a bulky group, while method B utilized polyaddition of a pseudo[2]rotaxane monomer to facilitate the control of the structure, i.e. the rotaxanation ratio.

Disulfide. -Sodium mono-and disulfide are synthesized with a selectivity >98% via the direct reaction of sulfur and Na in DME at 70°C (4-5 h) in the presence of a catalytic amount of aromatic hydrocarbons and ketone such as naphthalene, anthracene, phenanthrene, and benzophenone. -(TAKATA*, T.; SAEKI, D.; MAKITA, Y.; YAMADA, N.; KIHARA, N.; Inorg. Chem. 42 (2003) 12, 3712-3714; Dep. Appl. Chem., Coll. Eng., Osaka Prefect. Univ., Osaka 599, Japan; Eng.) -W. Pewestorf 37-015