1,2-Dithiaethane-1,2-bisthiol

Bright light-yellow liquid similar to olive oil, pungent odor. Somewhat less easily decomposed than H2S2 and H2S3; like these, it is converted on prolonged standing into homologs richer in sulfur. No definite melting point; solidifies at about —85°C to a white, glassy mass which gradually softens over a fairly wide temperature range when heated. Cracked by heating to lower hydrogen sulfides, particularly H3S. d (20°C) 1.582.

Tetrasulfane is obtained from crude sulfane in the apparatus shown in Fig. 157. The modified Utzinger tube h, the lower part of which is flattened to increase the vaporization surface as much as possible (see cross section), is surrounded by a heating jacket and carries a separatory funnel t and a 500-ml. flask r. The attached condenser K1 and the spiral condenser K 2 (which is identical to that used in trisulfane purification and has a toroidal expansion and an outlet to the receiver u) are provided with separate constant-temperature circulating systems. Again, condenser hs is connected to trap / , which is immersed in a Dry Ice-methanol mixture. Trap / adjoins double trap I, cooled with liquid nitrogen, which is connected to a high-vacuum pump. The connecting sections of the condensers are covered with asbestos insulation^ and￡a.