Nitrogen → 1,2,4,5-Benzenetetrathiol

HRID 1639148

Reaction equation

HRID 1639148 reaction equation
[Li].C([S:4][C:5]1[CH:10]=[C:9]([S:11]CC)[C:8]([S:14]CC)=[CH:7][C:6]=1[S:17]CC)C.N#N.[NH4+].[Cl-]>C(N)CC>[SH:4][C:5]1[CH:10]=[C:9]([SH:11])[C:8]([SH:14])=[CH:7][C:6]=1[SH:17]

Participants

6

Reactant 4

HCID 947NitrogenHCID 25517Ammonium ChlorideHCID 3028194Lithium2×HCID 126017611,2,4,5-Tetrakis(ethylsulfanyl)benzene

Product 1

HCID 127192181,2,4,5-Benzenetetrathiol

Reagents, catalysts & solvents 1

HCID 7852PropylamineSolvent2×

Conditions

Temperature
10 °C

Procedure

In a 3-1 sulfonating flask, 1,850 ml of dry n-propylamine and 9.6 g of granulated lithium are initially introduced under a nitrogen inert atmosphere. The mixture is stirred at room temperature until the blue colour persists, and 55.0 g of solid 1,2,4,5-tetraethylthiobenzene are then added. A slight exothermic reaction sets in, which is kept under control by cooling with an ice-bath to prevent the inside temperature of pg,7 the solution from exceeding 38° C. After the exothermic reaction has subsided, stirring is continued for 16-20 hours under a gentle stream of N2, a further 400 mg of lithium are then added, and the mixture is heated at the reflux temperature for half an hour. The mixture is then cooled to 10° C. and 18.5 g of dry NH4Cl are added in portions. The mixture is heated to the boiling temperature of propylamine, about 1,500 ml of which are distilled off. The suspension, which has become viscous and greenish, is cooled to 5° C. and brought to a pH of 1 by the dropwise addition of 5N HCl. The temperature should not exceed 10° C. during this addition. The 1,2,4,5-tetramercaptobenzene which precipitates during the acidification is extracted from the reaction mixture with 1 times 1 liter and 2 times 500 ml of chloroform under an inert gas, the organic phase is dried with Na2SO4 and then evaporated to half its volume and cooled to -21° C. Tetramercaptobenzene precipitates as slightly greenish crystals. Yield: 20.5 g (57.5% of theory). Melting point (m.p.): 139°-142° C.

Workup

  1. additionare then added
  2. customA slight exothermic reaction sets in, which
  3. temperatureby cooling with an ice-bath
  4. customfrom exceeding 38° C
  5. customAfter the exothermic reaction
  6. temperaturethe mixture is heated at the reflux temperature for half an hour
  7. distillationare distilled off
  8. temperaturegreenish, is cooled to 5° C.
  9. additionbrought to a pH of 1 by the dropwise addition of 5N HCl
  10. additionThe temperature should not exceed 10° C. during this addition
  11. customThe 1,2,4,5-tetramercaptobenzene which precipitates during the acidification
  12. extractionis extracted from the reaction mixture with 1 times 1 liter and 2 times 500 ml of chloroform under an inert gas
  13. dry with materialthe organic phase is dried with Na2SO4
  14. customevaporated to half its volume
  15. temperaturecooled to -21° C
  16. customTetramercaptobenzene precipitates as slightly greenish crystals
  17. custom139°-142° C.

Sources & evidence

ORD record
ord-845c4d4466b442e6a3c06a5a3d8369dd
Source dataset
uspto-grants-1989_11
Patent number
US04882415

Linked notes

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