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ChemicalBook CAS DataBase List 1,1,3,3-Tetramethylurea
632-22-4

1,1,3,3-Tetramethylurea synthesis

6synthesis methods
The reaction of dimethylamine with phosgene in the presence of e. g. 50 % sodium hydroxide solution and subsequent extraction with 1,2-dichloroethane yields tetramethylurea in 95% yield.
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Yield:632-22-4 92%

Reaction Conditions:

in dichloromethane;water at 15 - 20;Large scale;

Steps:

1 Embodiment 1
To the three-mouth flask is added dimethylamine aqueous solution (40%, 3 . 81 kg, 33.8 μM), ice salt bath to control the temperature 15 °C following dropwise triphosgene (773.4 g, 2.6 μM) of the dichloromethane solution, after the drop to, the natural recovery of the reaction liquid to room temperature to continue the reaction 2 - 3 hours, after the reacting liquid clarification, liquid, DCM extraction the aqueous phase, and then combined dichloromethane phase, the combined dichloromethane uses full and salt water washing, and thereafter drying, filtering, concentrating, oil pump vacuum distillation and drying to obtain 836 g colorless liquid, GC purity is greater than 99%, yield is 92%.

References:

Suzhou Haofan Biological Co., Ltd.;Jiang Zhaoqin;Li Honglin CN108558706, 2018, A Location in patent:Paragraph 0052-0054; 0057; 0058; 006; 0062; 0065; 0066

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