Diethylene Glycol Monomethyl Ether → Ethylenediamine, N-(4-aminophenyl)-

Temperature

189 °C

A mixture of p-diaminobenzene dihydrochloride (20.1 g, 0.11 mole), 2-oxazolidinone (17.4 g, 0.20 mole) and 100 ml of 2-(2-methoxyethoxy)ethanol was heated to 189° C. in an oil bath while being vigorously stirred mechanically. After two and one-half hours, all gas evolution had ceased and the dark purple reaction mixture was allowed to cool to room temperature. Most of the solvent was removed in vacuo while applying heat (95° C./10 mm Hg) to give a viscous, dark purple oil. After dissolution of the crude triamine dihydrochloride in 100 ml of a 10 percent aqueous sodium hydroxide solution, the free amine was extracted with three portions of chloroform. During the extraction, solid sodium chloride was added to help break up the emulsion which formed. The combined chloroform portions were dried over anhydrous potassium carbonate and filtered. After removal of the solvent in vacuo, approximately 20 g of the crude amine was obtained as a dark yellow oil. Kugelrohr distillation (bulb to bulb) at 160° C. to 190° C. (0.1 mm Hg) afforded a 29 percent yield of the triamine as a pale yellow oil. The product structure was confirmed by spectral studies.

1. temperatureto cool to room temperature
2. customMost of the solvent was removed in vacuo
3. temperaturewhile applying heat (95° C./10 mm Hg)
4. customto give a viscous, dark purple oil
5. extractionthe free amine was extracted with three portions of chloroform
6. extractionDuring the extraction, solid sodium chloride
7. additionwas added
8. customformed
9. dry with materialThe combined chloroform portions were dried over anhydrous potassium carbonate
10. filtrationfiltered
11. customAfter removal of the solvent in vacuo

ORD record

ord-a76af0a7c6dd4637b69558bc695b1f1f

Source dataset

uspto-grants-1983_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04381401