93138-75-1

Upstream product

• 106-49-0 p-toluidine 
• 88-10-8 N,N-diethylcarbamyl chloride 
• 97600-24-3 3,3-diethyl-1-(4-tolyl)-1-nitrosourea 
• 19873-46-2 N-Methyl-N'-(4-tolyl)harnstoff 
• 32315-10-9 bis(trichloromethyl) carbonate 
• 109-89-7 diethylamine 
• 201230-82-2 carbon monoxide 
• 622-59-3 1-isothiocyanato-4-methylbenzene 
• 99-99-0 1-methyl-4-nitrobenzene 
• 13939-06-5 molybdenum hexacarbonyl 
• 622-58-2 p-Tolylisocyanate 

Downstream Products

• 15441-96-0 N,N-diethyl-N'-(2-chloro-4-methylphenyl)urea 
• 97600-24-3 3,3-diethyl-1-(4-tolyl)-1-nitrosourea 
• 105363-75-5 C₂₄H₃₄N₄O 

Relevant academic research and scientific papers

Visible-light-promoted oxidative desulphurisation: A strategy for the preparation of unsymmetrical ureas from isothiocyanates and amines using molecular oxygen

A green and efficient visible-light promoted oxidative desulphurisation protocol has been proposed for the construction of unsymmetrical ureas under mild conditions with broad substrate scope and good functional group tolerance. Most appealingly, the reaction can proceed smoothly without adding any strong oxidants. Control experiments and computational studies support a mechanism involving water-assisted in situ generation of thioureas and photocatalytic oxidative desulphurisation. The present method provides a promising synthesis strategy for the formation of diverse and useful unsymmetrical urea derivatives in the fields of pharmaceutical and synthetic chemistry.

Pd/C-catalyzed reductive carbonylation of nitroaromatics for the synthesis of unsymmetrical ureas: One-step synthesis of neburon

A Pd/C catalyzed reductive carbonylation of nitroarenes for the synthesis of unsymmetrical ureas has been developed. Using inexpensive and stable nitroarenes as the substrates, a series of unsymmetrical ureas were produced in moderate to good yields. A range of functional groups including thioethers, halides and vinyl were compatible with this reaction. As a heterogeneous catalyst, Pd/C was recycled and reused four times without losing activity. Notably, urea-based herbicide neburon was prepared in 64% yield under our standard conditions.

Efficient Direct Halogenation of Unsymmetrical N -Benzyl- and N -Phenylureas with Trihaloisocyanuric Acids

A simple and efficient methodology for the direct halogenation of N -phenylureas was developed using trihaloisocyanuric acids in acetonitrile at room temperature. This protocol proved to be effective for the construction of N -phenylureas with different patterns of substitution. Additionally, less reactive N -benzylureas were halogenated in the presence of a mixture of trifluoroacetic acid and acetonitrile at room temperature.

Synthesis of unsymmetrical ureas by sulfur-assisted carbonylation with carbon monoxide and oxidation with molecular oxygen under mild conditions

With ambient pressure of carbon monoxide and oxygen at room temperature, N,N-dialkyl-N′-arylureas were selectively accessible from secondary amines, aromatic amines, and sulfur in good to excellent yields. For example, N-butyl-N-methyl-N′-(3,4-dichlorophenyl)urea, which is used as a herbicide (neburon), was afforded successfully from butylmethylamine (2 equiv), 3,4-dichloroaniline (1 equiv) and sulfur (1 equiv) in 79% (21.8 g) yield using carbon monoxide (0.1 MPa) and oxygen (0.1 MPa) at 20°C in DMF. Georg Thieme Verlag Stuttgart.

Carbonyldiimidazole-mediated lossen rearrangement

[Chemical Equation Presented] Carbonyldiimidazole (CDI) was found to mediate the Lossen rearrangement of various hydroxamic acids to isocyanates. This process is experimentally simple and mild, with imidazole and CO 2 being the sole stoichiometric byproduct. Significant for large-scale application, the method avoids the use of hazardous reagents and thus represents a green alternative to standard processing conditions for the Curtius and Hofmann rearrangements.

A Facile and High-yielding Preparation of 1-Aryl-3,3-dialkylureas

A convenient procedure for the preparation of 1-aryl-3,3-dialkylureas using bis(trichoromethyl) carbonate ('triphosgene') is described.

Transnitrosation by N-aryl-N-nitrosoureas; NO-carrying O-nitrosoisourea

Transfer of nitroso groups, so-called transnitrosation, from aromatic N-nitroso compounds such as N-nitrosoureas, N-nitrosamides and N-nitrosamines, to aromatic amines or ureas was observed under non-acidic conditions at room temperature. Sterically hindered 3,3-dibenzyl-1-(4-tolyl)-1-nitrosourea (1a) rapidly nitrosates indoline, N-alkylanilines or 3-methyl-1-(4-tolyl)urea to give their N-nitroso derivatives. In the case of N,N-dimethylanilines, nitrosative demethylation occurs to give N-methyl-N-nitrosanilines. The transnitrosation is accelerated by electron-releasing groups on the nitroso acceptors, N-alkylanilines. The transnitrosation mechanism is considered to be as follows: N-nitrosourea (1) thermally decomposes to nitric oxide and ureidyl radical followed by formation of an O-nitrosoisourea intermediate (10), which acts as an NO-carrying agent and nitrosates anilines or ureas.