Hydrochloric Acid → Ethanedithioamide, N,N'-bis(2-hydroxyethyl)-

Temperature

35 °C

Into a 100 ml round-bottomed flask, equipped with a magnetic stirrer, condenser, and heating bath, were placed 2.4 g (0.02 mol) of dithiooxamide and a solution of pyridine (1.6 g, 0.02 mol) dissolved in methanol (40 ml). The reaction mixture was heated, with stirring, at 35° C. for 30 minutes. Ethanolamine (1.2 g, 0.02 mol) was added, and the solution was stirred for an additional 3 hours at 35° C. The crude reaction mixture was cooled to room temperature, and the acidity was adjusted to a pH of about 2 by the addition of 37% HCl (aqueous). Silica gel (10 g) was added to the solution, and the solvent was removed under reduced pressure. The dry residue of silica gel with absorbed product mixture was added to a chromatography column. The products were eluted with an ethyl acetate/hexane mixture to separate the monosubstituted product, which was eluted first, from the disubstituted dithiooxamide. The yield of N-(2-hydroxyethyl)dithiooxamide was 1.1 g (7.0×10- 3 mol, 34% yield). In addition, 0.8 g (4.0×10-3 mol, 38% yield) of N,N'-di(2-hydroxyethyl)dithiooxamide was isolated. The mole ratio of monosubstituted to disubstituted dithiooxamide was 1.8:1.

1. customInto a 100 ml round-bottomed flask, equipped with a magnetic stirrer, condenser
2. temperatureheating bath
3. temperatureThe reaction mixture was heated
4. stirringthe solution was stirred for an additional 3 hours at 35° C
5. customThe crude reaction mixture
6. temperaturewas cooled to room temperature
7. additionSilica gel (10 g) was added to the solution
8. customthe solvent was removed under reduced pressure
9. additionThe dry residue of silica gel with absorbed product mixture was added to a chromatography column
10. washThe products were eluted with an ethyl acetate/hexane mixture
11. customto separate the monosubstituted product, which
12. washwas eluted first, from the disubstituted dithiooxamide

ORD record

ord-abc6e1a28ce544909c9ecc9e927079c4

Source dataset

uspto-grants-1991_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05041654