Carbon Disulfide → Perhydrobenzimidazole-2-thione

A solution of carbon disulfide (1.1 mL, 17.9 mmol) and CH2Cl2 (10 mL) was treated dropwise with cis-1,2-diaminocyclohexane 20-1 (Aldrich) (2.0 g, 17.5 mmol) while maintaining the reaction mixture temperature below 20° C. with an ice bath. The reaction mixture was stirred at ambient temperature for 2.0 h after the addition was complete. Concentration followed by refluxing the resulting solid in H2O (20 mL) for 20 h gave a yellow solution. The cooled solution was extracted with CH2Cl2 and the CH2Cl2 portion was dried (MgSO4) and concentrated. The pale yellow solid was recrystallized from CH2Cl2 /ether to give 20-2 as a pale yellow solid. mp=164-166° C.

1. temperaturewhile maintaining the reaction mixture temperature below 20° C. with an ice bath
2. additionafter the addition
3. concentrationConcentration
4. temperatureby refluxing the resulting solid in H2O (20 mL) for 20 h
5. customgave a yellow solution
6. extractionThe cooled solution was extracted with CH2Cl2
7. dry with materialthe CH2Cl2 portion was dried (MgSO4)
8. concentrationconcentrated
9. customThe pale yellow solid was recrystallized from CH2Cl2 /ether

ORD record

ord-4ea14fb098a94fbfa362012e502f5820

Source dataset

uspto-grants-1999_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05929120