2645-37-6

Usage

Synthesis Reference(s)

Tetrahedron Letters, 29, p. 2525, 1988 DOI: 10.1016/S0040-4039(00)86102-X

Upstream product

• 110-89-4 piperidine 
• 20950-96-3 (4-methoxyphenyl)carbamic acid phenyl ester 
• 5416-93-3 4-Methoxyphenyl isocyanate 
• 10349-38-9 p-methoxyphenylisonitrile 
• 104-94-9 4-methoxy-aniline 
• 7451-55-0 ethyl 4-methoxyphenylcarbamate 

Downstream Products

• 1227-44-7 N,N'-bis(4-methoxyphenyl)urea 
• 14803-72-6 methyl N-(4-methoxyphenyl)carbamate 

Relevant academic research and scientific papers

Rhodium-Catalyzed Oxidative Coupling Reaction of Isocyanides with Alcohols or Amines and Molecular Oxygen as Oxygen Source: Synthesis of Carbamates and Ureas

The first Rh-catalyzed aerobic oxidative coupling reaction of isocyanides with alcohols or amines has been developed. The reaction takes place under very mild conditions, by using air as the terminal oxidant and oxygen-atom source. It provides a simple, efficient, and general method for the construction of N-arylcarbamates and ureas in an atom-economic manner. Moreover, the new mechanism, involving α-diazocarbonyl compounds as carbene precursors and a RhI/RhIIIcatalytic cycle with oxygen, might open up new avenues in rhodium chemistry.

Synthesis of 11C-labelled ureas by palladium(II)-mediated oxidative carbonylation

Positron emission tomography is an imaging technique with applications in clinical settings as well as in basic research for the study of biological processes. A PET tracer, a biologically active molecule where a positron-emitting radioisotope such as carbon-11 has been incorporated, is used for the studies. Development of robust methods for incorporation of the radioisotope is therefore of the utmost importance. The urea functional group is present in many biologically active compounds and is thus an attractive target for incorporation of carbon-11 in the form of [11C]carbon monoxide. Starting with amines and [11C]carbon monoxide, both symmetrical and unsymmetrical 11C-labelled ureas were synthesised via a palladium(II)-mediated oxidative carbonylation and obtained in decay-corrected radiochemical yields up to 65%. The added advantage of using [11C]carbon monoxide was shown by the molar activity obtained for an inhibitor of soluble epoxide hydrolase (247 GBq/μmol-319 GBq/μ mol). DFT calculations were found to support a reaction mechanism proceeding through an 11C-labelled isocyanate intermediate.

A practical synthesis of ureas from phenyl carbamates

Using DMSO as solvent, a mild and efficient procedure for the synthesis of unsymmetrical N,N'-disubstituted ureas from phenyl carbamates is described. The carbamates are treated with a stoichiometric amount of amine at ambient temperature, generating the

sYNTHESIS OF N,N'-DISUBSTITUTED UREAS FROM CARBAMATES

A simple synthesis of N,N'-disubstituted ureas from carbamates is described involving displacement of an alkoxy group by the magnesium salt of an amine generated in situ by treatment with ethylmagnesium bromide.