76-06-2

A kinetic study of the chlorination of nitromethane to trichloronitromethane (chloropicrin) was made.The rate of production of chloropicrine in the pH 6-8 range is first order in both nitromethane and hypochlorite anion.The kinetic dependence on halogenating reagent is a new observation and involves hypochlorite anion acting as a general base.Around pH 12 and above, the mechanism changes to a rate-controlling step of reaction between nitromethane anion or a chlorinated nitromethane anion and hypochlorous acid.

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The nitration reaction of trichloroethene (1) to main products trichloronitroethene (TCNiE 2, up to 60.8 %, by GC), 1,1,2,2-tetrachloro-1-nitroethane (8, up to 25.1 %, by GC), and 1,2,2-trichloro-2-nitroethyl [chloro(nitro)methylene]azinate (9, up to 8.0 %, by GC) was comprehensively investigated and optimized. Different 1,1-diamino-2-chloro-2-nitroethenes, 2-nitroethoxyguanidines, and rare O-(1,2,2-trichloro-2-nitroethyl) oximes and carbimidoyl halides with unique formulas R-O-N=C(NO2)NRR1 and R-O-N=C(Hal)NRR1, respectively, were obtained from these nitration products in yields up to 91 %. The structure of (E)-morpholino(nitro)methanone O-(1,2,2-trichloro-2-nitroethyl) oxime (19) was proven by single-crystal X-ray diffraction analysis. In addition, the antimicrobial and antifungal activity of the synthesized compounds was examined. Notably, N-(1,2,2-trichloro-2-nitroethoxy)-3,4-dihydroisoquinoline-2(1H)carbimidoyl chloride (27) inhibited the growth of methicillin-resistant and sensitive Staphylococcus aureus with minimum inhibitory concentrations of 1.3 μg mL-1, and reduced the viability of the MCF-7 cancer cell line with an IC50 of 0.2 μg/mL. Trichloronitroethene and 1,2,2-trichloro-2-nitroethyl [chloro(nitro)methylene]azinate, nitration products of trichloroethene, are buildings blocks for O-(1,2,2-trichloro-2-nitroethyl) oximes, 1,1-diamino-2-chloro-2-nitroethenes, 2-nitroethoxyguanidines, and carbimidoyl halides. Some compounds show high activity against Staphylococcus aureus and reduce the viability of the MCF-7 cancer cell lines.

Organics enriched from samples of rain, snow, and glacier ice were analyzed to determine the chemical structure of the chloroorganic compounds that were most abundant in such media. Gas chromatography with atomic emission detection (GC-AED) was used to provide an overview of the presence of volatile and extractable chloroorganics at four sites in Europe and one site in Antarctica. Real samples and isomer-specific standards were then analyzed by gas chromatography with mass-spectrometric detection (GC-MS) to identify and confirm the structure of the chloroorganics that had been detected in the GC-AED analysis. The results revealed that of the volatile chloroorganics found in the samples, dichloronitromethane, a compound not previously reported to occur in the ambient environment, was often present in the highest concentration (up to 130 ng L-1). Chlorobenzenes were detected mainly as 1,4-dichlorobenzene and minor amounts of 1,3- and 1,2- dichlorobenzene and one isomer of tetrachlorobenzene (1,2,4,5- or 1,2,3,5- tetrachlorobenzene). Chlorinated alkyl phosphates, which were normally responsible for the largest peaks in the chlorine-specific chromatograms of hexane- or ether-extractable compounds, were present as tris(2- chloroethyl)phosphate, tris(1-chloro-2-propyl)phosphate, and one of the isomers bis(1-chloro-2-propyl)(3-chloro-1-propyl)phosphate er bis(1-chloro- 2-propyl)(2-chloro-1-propyl)phosphate. All of the chloroorganic compounds mentioned, i.e., dichloronitromethane, chlorobenzenes, and chlorinated alkyl phosphates, were detected at relatively remote sites in the northern hemisphere, whereas only chlorobenzenes were found in a reference sample of snow from Antarctica. Organics enriched from samples of rain, snow, and glacier ice were analyzed to determine the chemical structure of the chloroorganic compounds that were most abundant in such media. Gas chromatography with atomic emission detection (GC-AED) was used to provide an overview of the presence of volatile and extractable chloroorganics at four sites in Europe and one site in Antarctica. Real samples and isomer-specific standards were then analyzed by gas chromatography with mass-spectrometric detection (GC-MS)to identify and confirm the structure of the chloroorganics that had been detected in the GC-AED analysis. The results revealed that of the volatile chloroorganics found in the samples, dichloronitromethane, a compound not previously reported to occur in the ambient environment, was often present in the highest concentration (up to 130 ng L-1). Chlorobenzenes were detected mainly as 1,4-dichlorobenzene and minor amounts of 1,3- and 1,2-dichlorobenzene and one isomer of tetrachlorobenzene (1,2,4,5- or 1,2,3,5-tetrachlorobenzene). Chlorinated alkyl phosphates, which were normally responsible for the largest peaks in the chlorine-specific chromatograms of hexane- or ether-extractable compounds, were present as tris(2-chloroethyl)phosphate, tris(1-chloro-2-propyl)phosphate, and one of the isomers bis(1-chloro-2-propyl)(3-chloro-1-propyl)phosphate or bis(1-chloro-2-propyl)(2-chloro-1-propyl)phosphate. All of the chloroorganic compounds mentioned, i.e., dichloronitromethane, chlorobenzenes, and chlorinated alkyl phosphates, were detected at relatively remote sites in the northern hemisphere, whereas only chlorobenzenes were found in a reference sample of snow from Antarctica.