2986-17-6Relevant articles and documents
Method for preparing N, N '-diisopropylthiourea
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Paragraph 0017-0021, (2021/01/20)
The invention discloses a method for preparing N, N '-diisopropylthiourea, which relates to the technical field of organic chemical synthesis, and comprises the following steps: adding isopropylamineinto a reactor, controlling the temperature at 50-60 DEG C by using xylene as a solvent, and dropwisely adding carbon disulfide to react; after dropwise adding is finished, raising the temperature andkeeping the temperature for 1-2h for desulfurization, and reacting to generate hydrogen sulfide and N, N '-diisopropylthiourea; absorbing hydrogen sulfide with liquid caustic soda, cooling the N, N '-diisopropylthiourea solution, carrying out suction filtration, and drying to obtain the product. The method is simple in process, high in reaction selectivity and low in risk; meanwhile, tail gas iseasy to treat, generated sulfur can be absorbed by liquid caustic soda in an absorption tank, products can be sold out, and the tail waste treatment problem is solved; after the process is optimized,the yield of N, N '-diisopropylthiourea is increased to 99.55% or above, the purity reaches 99.90% or above, and the melting point is 145-147 DEG C.
N,N'-diisopropyl carbodiimide preparation method
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Paragraph 0037-0038; 0044; 0050, (2019/04/06)
The invention belongs to the technical field of organic synthesis and particularly relates to an N,N'-diisopropyl carbodiimide preparation method. The method includes steps: adopting isopropylamine and carbon disulfide to synthesize N,N'-diisopropyl thiourea in a solvent; subjecting the N,N'-diisopropyl thiourea to suction filtration, drying and primary oxidization; performing secondary oxidization reaction, adding a catalyst and an oxidant, and performing reaction for 1h at 60-65 DEG C; performing desulfurizing treatment, adding sodium sulfide solution into oxidation liquid, heating to 70-75DEG C, and performing reaction for 1-2h; adding caustic soda flakes to neutralize, washing, separating a water layer, adding a drying agent for drying, evaporating out the solvent, and performing vacuum rectification to obtain N,N'-diisopropyl carbodiimide. The N,N'-diisopropyl carbodiimide preparation method has advantages that wastewater recycling can be realized, emission is avoided, and accordingly environmental pollution is avoided; simplicity in feeding and aftertreatment, low production cost, high yield and high purity are realized.
Green process development for the synthesis of aliphatic symmetrical N,N'-disubstituted thiourea derivatives in aqueous medium
Jangale, Asha D.,Kumavat, Priyanka P.,Wagh, Yogesh B.,Tayade, Yogesh A.,Mahulikar, Pramod P.,Dalal, Dipak S.
supporting information, p. 236 - 244 (2015/10/29)
A highly efficient green process for the synthesis of N,N'-disubstituted aliphatic thiourea derivatives using primary aliphatic amines and carbon disulfide in aqueous medium at room temperature via a nonisothiocyanate route is described. This protocol illustrates the rapid preparation of N,N'-disubstituted aliphatic thiourea derivatives in excellent yields with some advantages such as no catalyst and simple workup without any side product formation. Moreover the new route is concise, chromatography-free, and adaptable to pilot-scale preparation.
