Hydrogen Peroxide → HCID 22465147, compound

Temperature

1 °C

A 5 liter 4-necked round-bottomed flask equipped with a mechanical stirrer and thermocouple thermometer was charged with 250 ml water and 43.3 g (0.232 mol) of 2,5-diethyl-2,5-dimethylimidazolidin-4-thione. In order to make the thione dissolve, 1.8 g NaOH was added. The solution was cooled to 0-2° C. with a dry ice-acetone bath. The flask was fitted with two additional funels. Simultaneously, a solution of 16.7 g NaOH in 100 ml water (total of 18.5 g or 0.464 mol of NaOH used) was added through one of the funnels and 105 ml (0.928 mol) of 30% H2O2 was added through the other funnel. The reaction mixture was stirred rapidly and required extensive cooling during the addition. The 5 liter flask was used to provide a large surface area for efficient cooling of the exothermic reaction. The heat of reaction was 269.2 Kcal/mol; 124. The addition was completed in 2 hours; the mixture was stirred an additional half hour. At the end of this time, TLC indicated that no thione remained. Then, 27.9 g of NaHSO3, (0.172 mol) was added to quench excess peroxide; this reaction is also somewhat exothermic (temperature increases from 26 to 43° C.). The reaction mixture was transferred to a 2 liter round-bottomed flask and the solvent removed with a rotary evaporator (aspirator pressure) to give a white residue. The residue was extracted with 850 ml of boiling ethanol. Then, 50 ml of toluene was added to the solution and 130 ml of water/ethanol/toluene azeotrope distilled to remove any remaining water. The solution was cooled and filtered to remove a small amount (˜1 g) of Na2SO4 and then the ethanol was removed on the rotary evaporator to give a syrup that crystallized on cooling to room temperature. The yield was 37.5 g (95%) mp 58-64° C. IR (nujol) 1705, 1659 cm-1. 1H NMR (CDCl3+D2O) ppm (combination of equal amounts of 2 sets of cis-trans pairs) 0.95-0.98 (m, 12H, CH3 on 4 ethyls), 1.27, 1.31, 1.34, 1.38 (4 s, total 12H, 4 CH3), 1.50-1.70 (m, 8H, CH2 on 4 ethyls). The singlets at 1.34 and 1.38 collapse to a singlet in D2O but now integrate 6H.

1. customA 5 liter 4-necked round-bottomed flask equipped with a mechanical stirrer
2. dissolutiondissolve
3. customThe flask was fitted with two additional funels
4. additionwas added through the other funnel
5. temperaturerequired extensive cooling during the addition
6. customto provide a large surface area
7. temperaturefor efficient cooling of the exothermic reaction
8. temperatureThe heat of reaction
9. additionThe addition
10. stirringthe mixture was stirred an additional half hour
11. customto quench excess peroxide
12. temperature(temperature increases from 26 to 43° C.)
13. customThe reaction mixture was transferred to a 2 liter round-bottomed flask
14. customthe solvent removed with a rotary evaporator (aspirator pressure)
15. customto give a white residue
16. extractionThe residue was extracted with 850 ml of boiling ethanol
17. additionThen, 50 ml of toluene was added to the solution and 130 ml of water/ethanol/toluene
18. distillationazeotrope distilled
19. customto remove any remaining water
20. temperatureThe solution was cooled
21. filtrationfiltered
22. customto remove a small amount (˜1 g) of Na2SO4
23. customthe ethanol was removed on the rotary evaporator
24. customto give a syrup that
25. customcrystallized
26. temperatureon cooling to room temperature

ORD record

ord-3efd84fe94b34793973eacbd19ce71a4

Source dataset

uspto-grants-2001_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06271340B1