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2,4-Dinitrochlorobenzene (DNCB) is an organic compound with the chemical formula (O 2 N) 2 C 6 H 3 Cl. It is a yellow solid that is soluble in organic solvents . It is an intermediate for the industrial production of other compounds.
The three possible arrangements of the nitro groups afford three isomers, 1,2-dinitrobenzene, 1,3-dinitrobenzene, and 1,4-dinitrobenzene. Each isomer has the chemical formula C 6 H 4 N 2 O 4 and a molar mass of about 168.11 g/mol. 1,3-Dinitrobenzene is the most common isomer and it is used in the manufacture of explosives .
Selected parameters: C=N, 128 pm; N-N, 1.38 pm, N-N-C(Ar), 119 [4] When 3-heptanone is added to a solution of 2,4-DNPH and heated, an orange-red precipitate forms. DNP-derived hydrazones have characteristic melting points, facilitating identification of the carbonyl. In particular, the use of DNPH was developed by Brady and Elsmie. [5]
The following is the reaction mechanism of a nucleophilic aromatic substitution of 2,4-dinitrochlorobenzene (1) in a basic solution in water. Nucleophilic aromatic substitution Since the nitro group is an activator toward nucleophilic substitution, and a meta director, it is able to stabilize the additional electron density (via resonance) when ...
Because acetic anhydride is not stable in water, the conversion is conducted under anhydrous conditions. To a decreasing extent, acetic anhydride is also prepared by the reaction of ketene with acetic acid at 45–55 °C and low pressure (0.05–0.2 bar). [8] H 2 C=C=O + CH 3 COOH → (CH 3 CO) 2 O (ΔH = −63 kJ/mol)
3,5-Dinitrobenzoyl chloride (C 7 H 3 ClN 2 O 5) is an organic compound with a melting point of 68–69 °C. [1] It is the acyl chloride of 3,5-dinitrobenzoic acid and like it is mainly used in the analysis of organic substances by derivatization .
Acetone and acetic anhydride ((CH 3 C(O)) 2 O) upon the addition of boron trifluoride (BF 3) catalyst: [11] (CH 3 C(O)) 2 O + CH 3 C(O)CH 3 → CH 3 C(O)CH 2 C(O)CH 3 A second synthesis involves the base-catalyzed condensation (e.g., by sodium ethoxide CH 3 CH 2 O − Na + ) of acetone and ethyl acetate , followed by acidification of the sodium ...
The LD50 (oral, rats) is 756 mg/kg. Animal studies have shown that 1,2,4-trichlorobenzene affects the liver and kidney, and is possibly a teratogen. [4] There is no regulated occupational exposure limit for chemical exposure, but the National Institute for Occupational Safety and Health recommends no greater exposure than 5 ppm, over an 8-hour workday.