Presence Of Phosphorus Trichloride Research Articles

THE INFLUENCE OF THE CONCENTRATION OF CHLORINE-CONTAINING CONDENSING AGENTS IN THE SYNTHESIS OF CARBOXYLIC ACID ANILIDESТ

Chlorine-containing condensing agents (PCl3, TiCl4, SiCl4) are widely used in the synthesis of carboxylic acid arylamides by the reaction of arylamines with carboxylic acids in stoichiometric amounts, and often in excess (40–150 mol % relative to the latter). To find the optimal amount of the condensing agent used, the acylation of aniline with 3-hydroxy-2-naphthoic acid in boiling ortho-xylene was studied in the PCl3 concentration range of 0–10 mol % from 3-hydroxy-2-naphthoic acid. It has been established that phosphorus tri-chlorochloride plays the role of a condensing agent and a catalyst, while 3-hydroxy-2-naphthoic acid anilide is formed along two routes with different rates, which can be separated kinetically. The first route includes the rapid synthesis of acid chloride, its interaction with aniline to obtain the target product. The second route is implemented due to phosphorous acid, which is formed from phosphorus trichloride and is a true acylation catalyst.
 The maximum yield of anilide 3-hydroxy-2-naphthoic acid decreases with increasing catalyst concentration, approximately propor-tional to the amount of aniline phosphite formed from it in the mass, which, apparently, is not reactive when interacting with the starting acid.
 Similar patterns were also found in the acylation of aniline with benzoic and salicylic acids in the presence of phosphorus trichloride; benzoic acid in the presence of titanium tetrachloride; 3-hydroxy-2-naphthoic acid in the presence of silicon tetrachloride. They allow a new look at the role of these products (PCl3, TiCl4, SiCl4) as condensing agents and/or ca­talysts in the synthesis of amides of carboxylic acids.
 Taking into account the obtained results, in practice it is better to use PCl3 as a catalyst in an amount not exceeding 2–2.5%, or even to replace it with phosphorous acid. This allows to completely get rid of the release of hydrogen chloride, significantly reduce the consumption rates for raw materials, simplify the entire technological process, reduce the amount of waste, ensure the yield of 3-hydroxy-2-naphthoic acid anilide close to quantitative, create a direct catalytic amidation technology that fully meets the criteria «green» chemistry processes.

Phosphoryl Trichloride-Method of Determination in Workplace Air.

The aim of this study was to develop and validate a method for determining phosphoryl trichloride in workplace air. The method is based on passing the tested air through a sodium carbonate-impregnated quartz fiber sampling filter. The substance collected on the sampling filter is extracted with ultrapure water. Phosphoryl trichloride is determined as chloride ions (the product of the hydrolysis of phosphoryl trichloride) in the obtained aqueous solutions by ion chromatography with conductometric detection. The developed method enables the determination of phosphoryl trichloride in the air in the concentration range from 0.004 to 0.160 mg/m3. The method is not applicable in the presence of phosphorus trichloride, hydrochloric acid, and its salts in the air. Good validation results were obtained. All requirements of the norm PN-EN 482 were met while developing and validating the method. This method can be used to measure workplace air in order to assess workers' occupational exposure.

Catalytic Synthesis of N-Aryladamantane-1-carboxamides Using Phosphorus Trichloride

N-Aryl(benzyl)adamantane-1-carboxamides were synthesized in 54–87% yields by reaction of adamantane-1-carboxylic acid with aromatic amines in the presence of phosphorus trichloride, 4-dimethylaminopyridine, and triethylamine on heating at 80°C for 8 h.

Selective Trifluoromethylthiolation and Trifluoromethylsulfinylation of Indoles with Sodium Trifluoromethanesulfinate Promoted by Phosphorus Reagents

Direct trifluoromethylthiolation and trifluoromethylsulfinylation reactions by using sodium trifluoromethanesulfinate were promoted by different phosphorus reagents to selectively occur under mild and transition‐metal‐free conditions. In the presence of phosphorus trichloride, sodium trifluoromethanesulfinate readily underwent a reaction with indole and its derivatives in N,N‐dimethylformamide (DMF) at room temperature to give 3‐trifluoromethylthiolated products in good yields. Trifluoromethylsulfinylation reactions, however, occurred at the C‐3 position when phosphorus oxychloride was used to give the corresponding sulfoxides in high yields. This protocol was further extended to the use of other sodium perfluoroalkanesulfinates.

Excited-state intramolecular proton transfer (ESIPT) inspired azole-quinoline based fluorophores: Synthesis and photophysical properties study

7-Hydroxy-3-(4-nitrophenyl)quinoline-6-carboxylic acid was obtained by the condensation reaction of p-amino salicylic acid and 4-nitrophenylmalonadialdehyde which was obtained from phenylacetonitrile through nitration, hydrolysis and Vilsmeier reaction. 7-Hydroxy-3-(4-nitrophenyl) quinoline-6-carboxylic acid was condensed with different o-aminophenols or o-aminothiophenol in ethanol in the presence of phosphorustrichloride. Synthesized quinoline contained benzimidazole and benzothiazole moieties. Photophysical behaviors of these compounds in solvents of different polarities were studied using UV–vis and fluorescence spectroscopy. The compounds showed single absorption in all the studied solvents. The dual emissions (normal emission and ESIPT emission) as well as large Stokes׳ shift emission pattern were observed for the synthesized fluorophores. The photophysical study shows that the emission properties of the compounds depend on the solvent polarity. The photophysical properties of the compounds were compared with structurally analogous ESIPT quinoline. Thermal stability of the compounds was studied using thermogravimetric analysis and results show that compounds are thermally stable up to 300°C. The synthesized quinoline derivatives were characterized using elemental analysis, FT-IR and 1H –NMR, 13C –NMR spectroscopy and mass spectral analysis.

ChemInform Abstract: Regiochemistry of the Reaction of 3,4,6‐Triisopropyl‐1,2‐benzoquinone with Phenylacetylene in the Presence of Phosphorus Trichloride.

The reaction of 3,4,6-triisopropyl-1,2-benzoquinone with phenylacetylene and phosphorus trichloride gave 2,6-dichloro-5,7,8-triisopropyl-4-phenyl-1,2λ5-benzoxaphosphinine 2-oxide whose structure was determined by X-ray analysis.

Regiochemistry of the reaction of 3,4,6-triisopropyl-1,2-benzoquinone with phenylacetylene in the presence of phosphorus trichloride

The reaction of 3,4,6-triisopropyl-1,2-benzoquinone with phenylacetylene and phosphorus trichloride gave 2,6-dichloro-5,7,8-triisopropyl-4-phenyl-1,2λ5-benzoxaphosphinine 2-oxide whose structure was determined by X-ray analysis.

Reaction of 3,6-di-tert-butyl-4,5-dichloro-1,2-benzoquinone with phenylacetylene in the presence of phosphorus trichloride

Reaction of 3,6-di-tert-butyl-4,5-dichloro-1,2-benzoquinone with phenylacetylene in the presence of phosphorus trichloride

TRIPOD-LIKE COMPOUNDS: SYNTHESES OF TRIS(p- OR o-AMINO PHENOXYMETHYL)-PROPANE, TRIS(p- OR o-AMINO PHENOXYETHYL)AMINE, AND THEIR SCHIFF BASE OR SALICYL DERIVATIVES

Tris(nitrophenoxymethyl)propane and tris(nitrophenoxy ethyl)amine, prepared by the reaction of trimethylol propane or triethanol amine with p- or o-chloronitrobenzene, were reduced to give the corresponding amines. The amines condensed with 2-pyridinecarboxaldehyde, 2-quinolinecarboxaldehyde, or salicylaldehyde to give the tripod Schiff bases. The tripodal salicylamides were obtained by condensation of salicylic acid with the amines in the presence of phosphorus trichloride.

Synthesis and properties of bis-arylides of 3-hydroxy-2-naphthoic acid, derivatives of 1,4-phenylenediamines

Bis arylides of 3-hydroxy-2-naphthoic acid were synthesised by heating a pyridine solution of 3-hydroxy-2-naphthoic acid and 1,4-phenylenediamine or its derivatives, in the presence of phosphorus trichloride. The suitability of chlorobenzene in this reaction was also demonstrated.

Synthesis of 2-methyl-4(5)-nitro[15N1(3)]imidazole from 2-methyl-4(5)-nitroimidazole

A simple four-stage conversion of 2-methyl-4(5)-nitroimidazole to 2-methyl-4(5)-nitro[15N1(3)]imidazole is reported. The method consists in N-nitration of the initial compound to 2-methyl-1,4-dinitroimidazole, treating the latter with [15N]glycine and N-dealkylation of the obtained (2-methyl-4-nitro[15N1]imidazol-1-yl)acetic acid through its bromination in the presence of phosphorus trichloride, followed by the hydrolysis of the non-isolated intermediate.

ChemInform Abstract: Synthesis of Pyrroles Under Mild Conditions Using PCl3, Ketones, and Alkylhydrazines.

AbstractCyclization of the hydrazones (III) in the presence of phosphorus trichloride gives a mixture of the pyrroles (IV) and (V) which are also obtained directly from the ketones (I) and the hydrazines (II).

ChemInform Abstract: Reactions of Trialkyltrithiophosphites with Ketones in the Presence of Phosphorus Trichloride.

ChemInform Abstract: Reactions of Trialkyltrithiophosphites with Ketones in the Presence of Phosphorus Trichloride.

Synthesis of some N-substituted salicylamides structurally related to certain antimicrobials.

The condensation of 5-nitrosalicoylchloride and 5-sulphamoylsalicylic acid with certain amines is described. Reacting the acid chloride with 3-amino-2-oxazolidone, 4-aminophenazone, thiosemicarbazide, 1-aminohydantoin and 2-aminopyridine yielded the correspondong N-substituted 5-nitrosalicylamides (1a-c), while with semicarbazide a disubstituted product type 2 was obtained. On the other hand, when 5-sulphamoylsalicylic acid was condensed with o-chloroaniline, m-chloroaniline and 4-aminophenazone in the presence of phosphorus trichloride, instead of affording the expected condensation products type 3, it yielded N1N5-disubstituted 5-sulphamoylsalicylamides (4a-c). The synthesized compounds were screened for antimicrobial activity.

Synthesis of some 1-substituted 2,5-diphenylimidazoles

The synthesis of 1,2,5-triphenylimidazole derivatives was accomplished by reaction of ω-benzamidoacetophenone with primary aromatic amines in the presence of phosphorus trichloride.

Isomerization of 1-oxo-1-chlorophospholenes in the presence of phosphorus trichloride

The isomerizing action of phosphorus trichloride on phospholene derivatives was observed. It was shown that mixtures of isomers, with predominance of 2-phospholene, are formed when isomerically pure 1-oxo-1-chlorophospholenes are heated in the presence of phosphorus trichloride.

Photochemical cross-linking of polyethylene fibre in the presence of phosphorus trichloride

Photochemical cross-linking of polyethylene fibre in the presence of phosphorus trichloride

1,3,4-Thiodiazole誘導体に関する研究 (第5報)

By the condensation of malonic or succinic ester chlorides respectively with thiosemi-carbazide, in the presence of phosphorus trichloride, ethyl 2-amino-1, 3, 4-thiodiazole-5-acetate and methyl 2-amino-1, 3, 4-thiodiazole-5-propionate were obtained. Their hydrolyses afforded the corresponding acids. Their respective acid amides and acid hydrazides were also prepared.