67488-19-1

Upstream product

• 67488-20-4 1,3-dibenzoyl-1,3-dimethylurea 
• 96-31-1 N,N'-Dimethylurea 
• 98-88-4 benzoyl chloride 
• 88333-03-3 Benzyl isocyanide 
• 119072-55-8 tert-butylisonitrile 
• 80-48-8 methyl p-toluene sulfonate 
• 5378-17-6 3-hydroxy-5-phenyl-1,2,4-thiadiazole 

Relevant academic research and scientific papers

Decomposition of N′-benzoyl-N-nitrosoureas in aqueous media

The decomposition of N′-benzoyl-N-methyl-N-nitrosourea (BMNU) in aqueous media over the 0-14 pH range has been studied. In basic and neutral media (6 a = 7.8) and subsequent decomposition of the conjugate base of the thus formed nitrosourea, via an intermediate benzoyl isocyanate. Support for this mechanism is provided by the presence of N,N′-dibenzoylurea in the final reaction mixtures, as the result of the trapping of benzoyl isocyanate with benzamide generated from hydrolysis of the former. The hydrolysis of BMNU takes place through three competitive pathways: spontaneous decomposition of the conjugate base of BMNU, and buffer-catalyzed and hydroxide ion catalyzed water addition to the carbonyl group of the deprotonated nitrosourea. N′-Benzoyl-N,N′-dimethyl-N-nitrosourea (BDMNU), a benzoyl nitrosourea lacking the acidic proton of BMNU, is hydrolyzed in basic media by attack of hydroxide ion on the carbonyl group of the urea. In acid media (0 pH 6), BMNU gives only deamination products, differing from the reported behavior of other N-nitroso compounds and of the isoster nitrosoguanidine, in which denitrosation is almost quantitative. The reaction is acid-catalyzed in the 0-2.5 pH range and pH-independent in the 3-5 pH range. The presence of general acid catalysis (a = 0.60), the absence of nucleophilic catalysis, and the thermodynamic activation parameters for the reaction support the mechanism proposed in the literature for the deamination of N-nitrosoureas in acidic media. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.

First practical synthesis of formamidine ureas and derivatives

(Matrix presented) Isonitriles and ureas undergo a condensation reaction in the presence of acid chlorides to give formamidine ureas, for which no general synthetic routes currently exist. A mechanism is proposed in which the key intermediate is an electrophilic adduct of isonitrile and acid chloride. The process is tolerant of moderate variability in the nature of the components, and access to formamidine ureas of varying substitution patterns is further enhanced by a facile exchange reaction with amines.

Cyclic Meso-ionic Compounds. Part 23. Novel Chemistry of 1,2,4-Thiadiazoles and Their Transformation into Meso-ionic 1,2,4-Thiadiazolium Derivatives

Representatives of two new classes of meso-ionic heterocycles have been synthesised, the 1,2,4-thiadiazolium-3-olate (8) and the 1,2,4-thiadiazolium-3-tosylaminide (25).The reactions of 1,2,4-thiadiazoles and nucleophiles follow two general pathways: (i) reductive transformation to N-thiobenzoyl derivatives and (ii) elimination of elemental sulphur and the formation of N-benzoyl derivatives.A mechanistic rationale is proposed for the operation of pathways (i) and (ii).Earlier views on the oxidative formation of certain 1,2,4-thiadiazoles are corrected.A novel synthetic route to heterocycles containing sulphur-nitrogen bonds is described. 1,2,4-Thiadiazoles are formed by oxidation of N-thiobezoylureas and N-thiobenzoylguanidines by bis(4-methoxyphenyl) telluroxide.