反应详情

Dimethylammonium dimethyldithiocarbamate (33.2 grams, 0.20 mole), formaldehyde (16.2 grams of 37% aqueous solution, 0.20 mole), 2,4-pentanedione (20.0 grams, 0.20 mole), and carbon disulfide (15.2 grams, 0.20 mole) were dissolved in methanol (100 ml.). The temperature of the resulting reaction was kept below 27° C. with ice cooling. After three hours at 22° C.-29° C., the reaction mixture was cooled in ice and the precipitated product was filtered off, washed with cold methanol and water, and dried in air. The crude product, melting at 69.5° C.-71.5° C. (prior sintering) weighed 37.3 grams (80%). Repeated precipitation of the material from carbon tetrachloride solution by the addition of hexane gave pure 2-(1-hydroxyethylidene)-3-oxobutyl dimethyldithiocarbamate melting at 70° C.-72° C. The structure was determined from infrared and nuclear magnetic resonance spectra and elemental analysis.

1. customThe temperature of the resulting reaction
2. customwas kept below 27° C. with ice cooling
3. temperaturethe reaction mixture was cooled in ice
4. filtrationthe precipitated product was filtered off
5. washwashed with cold methanol and water
6. customdried in air
7. customprecipitation of the material from carbon tetrachloride solution
8. additionby the addition of hexane