88333-03-3Relevant articles and documents
One-Pot Synthesis of Thiocarbamates
Barther, Dennis,Malliaridou, Triantafillia,Meier, Michael A. R.,Moatsou, Dafni,Waibel, Kevin A.
supporting information, p. 4508 - 4516 (2021/08/30)
An efficient isocyanide-based synthesis of S-thiocarbamates was discovered and thoroughly investigated. The new reaction protocol is a one-pot procedure and allows the direct conversion of N-formamides into thiocarbamates by initial dehydration with p-toluene sulfonyl chloride to the respective isocyanide and subsequent addition of a sulfoxide component. Contrary to recent literature, which also uses isocyanides as starting material, but with other sulfur reagents than sulfoxides, in this protocol, no isolation and purification of the isocyanide component is necessary, thus significantly decreasing the environmental impact and increasing the efficiency of the synthesis. The new protocol was applied to synthesize a library of sixteen thiocarbamates, applying four N-formamides and four commercially available sulfoxides. Furthermore, experiments were conducted to investigate the reaction mechanism. Finally, four norbornene-based thiocarbamate monomers were prepared and applied in controlled ring-opening metathesis polymerization (ROMP) reactions. The polymers were characterized by size-exclusion chromatography (SEC) and their properties were investigated utilizing differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).
Method for preparing isonitrile compound
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Paragraph 0056-0061, (2021/01/30)
The invention discloses a method for preparing an isonitrile compound, and belongs to the field of organic synthesis. According to the method, sodium chlorodifluoroacetate or potassium bromodifluoroacetate is used as a difluoromethyl source and is condensed with primary amine under the action of alkali to obtain an isocyanide target product, so that isocyanide is generated in situ on the primary amine. The reaction raw materials, alkali and solvent used in the method are simple and easy to obtain, wide in source and convenient to operate, do not need special storage and use conditions, the method has the advantages of safety, low cost, high yield, simple process, environmental friendliness and the like, and has important application value in the fields of medicine, protein and polypeptidepreparation, pesticides, high polymer materials, dyes and the like.
A more sustainable and highly practicable synthesis of aliphatic isocyanides
Waibel,Nickisch,M?hl,Seim,Meier
supporting information, p. 933 - 941 (2020/02/21)
Synthesis protocols to convert N-formamides into isocyanides using three different dehydration reagents (i.e. p-toluenesulfonyl chloride (p-TsCl), phosphoryl trichloride (POCl3) and the combination of triphenylphosphane (PPh3) and iodine) were investigated and optimized, while considering the principles of green chemistry. Comparison of the yield and the E-factors of the different synthesis procedures revealed that, in contrast to the typically applied POCl3 or phosgene derivatives, p-TsCl was the reagent of choice for non sterically demanding aliphatic mono- or di-N-formamides (yields up to 98% and lowest E-factor 6.45). Apart from a significantly reduced E-factor, p-TsCl is cheap, offers a simplified reaction protocol and work-up, and is less toxic compared to other dehydration reagents. Thus, this procedure offers easier and greener access to aliphatic isocyanide functionalities.
