Chemical Properties
Centralite II, also known as 1,3-Dimethyl-1,3-diphenylurea, is a white to grey crystalline powder that is soluble in water, alcohol, acetone, and chloroform. This substance is commonly used as a burning rate moderator and stabilizer for smokeless powder, as well as a plasticizer for celluloid.
Uses
Detection of Methyl Centralite (MC) as gunshot residues (GSR) has been developed.
Description
1,3-Dimethyl-1,3-diphenylurea for Stabilizer and propellant, and production of intermediates of organic chemicals.
Preparation
1,3-Dimethyl-1,3-diphenylurea can be synthesized through the reaction of methylaniline and phosgene.
Application
Centralite II can be used as a stabilizer for smokeless powder, explosives, nitrates and smokeless fuels, as well as intermediates for fine chemicals.
Uses
1,3-Dimethyl-1,3-diphenylurea (methyl centralite) is a stabilizer in different types of ammunition. This compound is organic gunshot residue. It is the characteristic compound for which forensic analysts test determining if a person has discharged a firearm[1-2].
Flammability and Explosibility
Not classified
Synthesis
To a 10 mL Schlenk tube equipped with a magnetic stirring bar was charged with arylcarbamoyl chlorides (0.2 mmol, 1.0 equiv), and KHCO3 (40 mg, 0.4 mmol), and then Pd(PPh3)4 (0.01 mmol, 11.56 mg) were added. Finally, 1,4-dioxane (1.0 mL) was added to the mixture via syringe at room temperature under N2. The tube was sealed and put into a preheated oil bath a 100 °C for 48 h. The mixture was cooled to room temperature, quenched with water (5 mL), and diluted with ethyl acetate (5 mL). The layers were separated, and the aqueous layer was extracted with 2 × 5 mL of ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The crude product of 1,3-dimethyl-1,3-diphenylurea was purified by flash chromatography on silica gel (H), using 30-35% ethyl acetate/petroleum ether as the eluent.
storage
Store in original tightly closed containers in a dry, cool and well-ventilated area.
References
[1] Ricardo J. González. “Detection of organic gunshot residues from human hands using direct sample analysis-time of flight-mass spectrometry.” Journal of Mass Spectrometry 57 5 (2022).
[2] Patrick W. Fedick , Ryan M. Bain. “Swab touch spray mass spectrometry for rapid analysis of organic gunshot residue from human hand and various surfaces using commercial and fieldable mass spectrometry systems.” Forensic Chemistry 5 (2017): Pages 53-57.
