SANGER-RIEGEL. — PYEOSULPH. CHLORIDE-CHLORSULPH. ACID. 695 



tetrachloride, for much of this reagent escapes with the phosgene. The 

 pyrosulphuryl chloride is high, but it is clear that both bodies are formed 

 in the reaction and that chlorsulphonic acid is the chief product. 



2. 116 g. oleum (90 per cent) were added to 225 g. CCI4 (over twice 

 the theory) in 45 minutes, and the mixture fractioned after standing 

 over night. From 65° to 130°, 112 g. were obtained ; from 145° to 153°, 

 137 g., melting at —128°. There was little residue. The 137 g., treated 

 with 81 g. salt (120 per cent theory) gave 14 g. distillate at 56-57° 

 (23 mm.) melting at —37-36°. The residue was not examined. The 

 yield of crude mixture, 91 per cent, has been improved by excess of 

 carbon tetrachloride, and it is again shown that only a small amount of 

 pyrosulphuryl chloride is formed from a low oleum. 



3. 108 g. melted SOs (98.9 per cent) were added to 220 g. CCI4 in 

 45 minutes and fractioned after 48 hours. 165 g. were obtained up to 

 130° ; 106 g. from 139° to 141°, and there was little residue. By re- 

 distilling the first fraction, a little more was added to the second, giving 

 110 g., boiling mainly at 140°, melting at —41-40°. This treated 

 with salt and distilled gave 84 g. at 60° to 62° (25 mm.), melting at 

 —38-35°. The residue was not examined. The yield of crude pyro- 

 sulphuryl chloride, 84 g., is about 70 per cent of the theory. 



4. 175 g. oleum ^93.4 per cent) were added to 347 g. CCI4 in 90 

 minutes, the product standing over night. 176 g. were obtained up to 

 130° ; 189 g. between 130° and 152°, and the residue was slight. The 

 main fraction melted chiefly at —90°, but there was a residual solid not 

 melting until —45-40°. 103 g. of the main fraction, with 50 g. salt 

 (150 per cent theory) gave 39 g. distillate at 50-55° (21 mm.), melting 

 at— 43-38°. The distillation was continued up to 80° (bath, 150°), 

 which evidently caused decomposition, as there was much hydrochloric 

 acid in the U-tube, a little chlorine, and, from its melting point, con- 

 siderable sulphuryl chloride. The residue from the salt treatment was 

 distilled with 130 g. oleum (89.3 per cent), slightly in excess of the 

 theory. At 70-76° (21 mm.), most of the product, 64 g., came over, 

 but the heating was continued to 87° (bath, 153°). The U-tube con- 

 tained hydrochloric acid, chlorine, and sulphuryl chloride. On redistil- 

 lation, 56 g. were obtained at 75-78° (23 mm.), melting at —133-127°. 

 Considerable sulphuric acid was left in the flask, and in the U-tube 

 was some sulphuryl chloride. The yield of crude mixture, 189 g., is 

 about 75 per cent of the theory. The proportions of the two bodies, 

 39 g. and 56 g., are in the direction of those which should have been 

 recovered from 103 g. of crude mixture, —36 g. and 67 g. The decom- 

 position of the chlorsulphonic acid was in accord with the observations 

 of other workers and with those made later by ourselves. 



