Synthesis of 1,3-dioxolane derivatives

Chloral cyanomethylhemiacetal is converted to 2-trichloromethyl-4-imino-1,3-dioxolane under the influence of hydrogen chloride or pyridine. Acetone cyanohydrin reacts with chloral to give 2-trichloromethyl-4-imino-5,5-dimethyl-1,3-dioxolane, the hydrochloride of which in water gives 2-trichloromethyl-4-oxo-5,5-dimethyl-1,3-dioxolane.     

Peculiar Features of Reaction of 2-tert-Butoxy-5,6-benzo-1,3,2-dioxaphosphinin-4-one with Chloral. Steric Structure of 2-Chloro-3-trichloromethyl-6,7-benzo-1,4,2λ5-dioxaphopshepin-5-one 2-Oxide

The reaction of 2-tert-butoxy-5,6-benzo-1,3,2-dioxaphosphinin-4-one with chloral involves expansion of the six-membered heteroring to form 2-hydroxy-3-trichloromethyl-6,7-benzo-1,4,2⁵-dioxaphosphepin-5-one 2-oxide as a single diastereomer. The product was chlorinated with thionyl chloride to obtain (RS,SR)-2-chloro-3-trichloromethyl-6,7-benzo-1,4,2⁵-dioxaphosphepin-5-one 2-oxide.     

Photochemical chlorination of 2-trichloromethyl-1,3-dioxolane

The photochemical chlorination of 2-trichloromethyl-1,3-dioxolane proceeds only at the carbon atoms in the 4 and 5 positions. The structures of the resulting 2-trichloromethyl-4-chloro-and 2-trichloromethyl-4,5-dichloro-1,3-dioxolanes were proved by means of the IR spectra and chemical transformations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1611–1613, December, 1973.     

Isomerization of 2-trichloromethyl-4-methylene-1, 3-dioxolanes

The thermal isomerization of 2-trichloromethyl-4-methylene-1,3-dioxolanes was studied. This reaction may serve as a convenient method for the preparation of 2-trichloromethyl-4-methyl-5-alkyl(aryl)-1,3-dioxols.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 446–449, April, 1973.     

Microwave-assisted synthesis of 5-trichloromethyl substituted 1-phenyl-1H-pyrazoles and 1,2-dimethylpyrazolium chlorides

A series of five 5-trichloromethyl-1-phenyl-1H-pyrazoles and six 5-trichloromethyl-1,2-dimethylpyrazolium chlorides have been synthesized in 80-98% yield by environmentally benign microwave induced techniques involving the cyclocondensation of 4-alkoxy-1,1,1-trichloro-3-alken-2-ones [Cl₃C(O)C(R²)=C(R¹)OR, where R²=H, Me; R¹=H, alkyl, phenyl and R=Me, Et] with phenyl hydrazine and 1,2-dimethylhydrazine dihydrochloride, respectively, using toluene as solvent. The use of microwave and classical methods are comparable for making pyrazoles, but the formation of pyrazolium chlorides can be achieved in a significant shorter time, and in some cases better yield.     

Fused-s-triazino heterocycles IX. 1,3,4,6,9b-pentaazaphenalenes and 1,3,6,9b-tetraazaphenalenes: Amino and alkoxy derivatives

The trichloromethyl group served as a useful leaving group in nucleophilic displacement reactions by a variety of substituted amines and alcohols (the latter under base catalysis) on 2-trichloromethyl-5-methyl-1,3,4,6,9b-pentaazaphenalene ( 1a ) and 2-trichloromethyl-4-cyano-1,3,6,9b-tetraazaphenalene ( 2a ). The reaction conditions were mild and the yields of the corresponding 2-substituted amino and alkoxy derivatives were generally good.     

Synthesis and properties of derivatives of symtriazine. 17. Synthesis of 2-methyl-4,6-disubstituted and 2,4-dimethyl-6-substituted sym-triazines by reduction of the corresponding trichloromethyl derivatives

The reduction of trichloromethyl groups in sym-triazine derivatives to methyl groups is studied. It is shown that 2-R-4, 6-bis (trichloromethyl)-sym-triazines can be reduced to 2-R-4, 6-dirnethyl-sym-triazines with zinc dust in ethanol or with lithium aluminum hydride in THF. 2-Amino, N-substituted 2-amino-, and 2-alkoxy-4-trichloromethyl-6-R-sym-triazines are reduced to the corresponding methyl derivatives by boiling with lithium aluminum hydride in dibutyl ether.I. M. Gubkin State Petroleum and Gas Academy, Moscow 117917. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 667–673, May, 1995. Original article submitted March 23, 1995.     

Heterocyclization of ω-Bromo-2-trichloroacetyl Cycloalkanones to Isoxazole Derivatives

A new series of brominated 3,4-polymethylene-5-hydroxy-5-trichloromethyl-4,5-dihydroisoxazoles (2a–d) has been regiospecifically obtained from the reaction of ω-bromo-2-trichloroacetylcycloalkanones with hydroxylamine in 79–87% yield. Dehydration of the 5-hydroxydihydroisoxazoles 2a–d can be effected with concentrated sulfuric acid at 25 °C to give the regioisomeric brominated 3,4-polymethylene-5-trichloromethylisoxazoles (3a–d). In contrast, the dehydration of 5-hydroxydihydroisoxazoles with sulfuric acid in ethanol solution at 65 °C, for transformation of trichloromethyl to carboxyl group, was reproducible only with 9-bromo-3-trichloromethyl-3,3a,4,5,6,7,8,9-octahydrocycloocta[c]isoxazole-3-ol, 2d, leading to isoxazolecarboxylate 4d. The structural assignments of all isolated products are based on the analysis of their ¹H and ¹³C NMR spectral data.     

Chloromethyl-, dichloromethyl-, and trichloromethyl-1,2,4-triazines and their 4-oxides: method for the synthesis and tele-substitution reactions with C-nucleophiles

A simple procedure was developed for the synthesis of 1,2,4-triazines and their 4-oxides containing the ClCH₂, Cl₂CH, or CCl₃ group at position 3 by cyclization of 2-aryl-2-hydrazono-1-oximinoethanes with the corresponding chloroacetonitriles. The reaction pathway depends on the number of halogen atoms in the acetonitrile used. The reactions with trichloroacetonitrile, monochloroacetonitrile, and dichloroacetonitrile afford 3-trichloromethyl-1,2,4-triazines, 3-chloromethyl-1,2,4-triazine 4-oxides, and a mixture of the corresponding dichloromethyltriazines and their 4-oxides, respectively. The reactions of 3-trichloromethyl-1,2,4-triazines with indoles and phenols are accompanied by tele-substitution with elimination of halogen from the trichloromethyl group to give 5-indolyl- (or 5-hydroxyphenyl)-3-dichloromethyl-1,2,4-triazines.     

Synthesis and antimicrobial and antinociceptive activity of 4-substituted 2-trichloromethyl-3H-1,5-benzodiazepines

Russian Chemical Bulletin - The reaction of 1-substituted 4,4,4-trichloromethylbutane-1,3-diones with o-phenylenediamine afforded 4-substituted 2-trichloromethyl-3H-1,5-benzodiazepines with...     

Fused s-triazino heterocycles. X. Displacement reactions of 7,9-dibromo-2-tribromomethyl-5-trichloromethyl-1,3,4,6,9b-pentaazaphenalene and 7,9-dibromo-2,5-bis(tribromomethyl)- 1,3,4,6,9b-pentaazaphenalene

The preparation of 7, 9-dibromo-2-tribromomethyl-5-trichloromethyl-1, 3, 4, 6, 9b-pentaazaphenalene ( 1c ) and 7, 9-dibromo-2, 5-bis(tribromomethyl)-1, 3, 4, 6, 9b-pentaazaphenalene ( 1d ) is described. Reaction of 1c with various nucleophiles converted it to the corresponding 7, 9-dibromo-2, 5-bis-substituted derivatives, the tri-halomethyl groups serving as leaving groups. Displacement, first of one tribromomethyl group on 1d by pyrrolidine, and then by various nucleophiles on the remaining tribromomethyl group led to several mixed 2, 5-disubstituted derivatives.     

Synthesis of fluorine-containing tetrasubstituted pyrimidines from 1-cyano-2-chloro-2-trifluoromethylethylenes

The condensation of 1,1-dicyano- and 1-trifluoromethylthio-1-cyano-2-chloro-2-trifluoromethylethylenes with amidines of trifluoro- or trichloroacetic acid gave 2,4-bis(trifluoromethyl)(or 2-trichloromethyl-4-trifluoromethyl)-5-cyano(or 5-trifluoromethylthio)-6-aminopyrimidines. The corresponding substituted 1-methyl(or 1-phenyl)-6(1H)-pyrlmidineimines were synthesized by condensation of the same ethylenes with N-methyl (or N-phenyl)benzamidines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1680–1681, December, 1981.     

Synthesis and Properties of sym-Triazine Derivatives. 18. Synthesis of N-Substituted 2,4-Diamino-6-(benzothiazolyl-2-thiomethyl)-sym-triazines

The condensation of methyl benzothiazolyl-2-thioacetate with N-substituted biguanides in the presence of sodium methylate gave 2-amino-4-(RR'-amino)-6-(benzothiazolyl-2-thiomethyl)-sym-triazines. In a number of cases the 1,1-disubstituted 5-(benzothiazolyl-2-thioacetyl)biguanides could also be separated and these could be cyclized by refluxing in DMF to the corresponding substituted sym-triazines described. The latter type of compound was also synthesized by treating 2-amino-4-trichloromethyl-6-(benzothiazolyl-2-thiomethyl)-sym-triazine with primary and secondary aliphatic and heterocyclic amines or by the reaction of N-substituted 2,4-diamino-6-chloromethyl-sym-triazines with 2-mercaptobenzothiazole.     

Synthesis and properties of sym-triazine derivatives. 3. alkoxylation of 2-alkyl-4,6-bis(trichloromethyl)-sym-triazines containing higher alkyl radicals

Nucleophilic substitution reactions of trichloromethyl groups in 2-alkyl-4,6-bis-(trichloromethyl)-sym-triazines by alkoxy radicals were studied. It was shown that in the presence of sodium alcoholates, two CCl₃ groups are replaced, and the corresponding 2,4-dialkoxy-6-alkyl-sym-triazines are formed. The products of partial replacement, 2-alkoxy-4-trichloromethyl-6-alkyl-sym-triazines, were synthesized by heating the initial sym-triazines with alcohols in the presence of tertiary amines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1674–1677, December, 1984.     

HALOACETYLATED ENOL ETHERS: 16[5] REGIOSPECIFIC SYNTHESIS OF 5-TRICHLOROMETHYL-PYRAZOLES

ABSTRACT

The regiospecific synthesis and isolation of three series of 5-trichloromethyl-pyrazoles 2f–j, 3a–j and 4a–j from the cyclocondensation of 1,1,1-trichloro-4-alkoxy-3-alken-2-ones (1a–f) or trichloroacetyl containing β-diketones (1g–j) with dry hydrazine and phenyl-hydrazine is reported. It was established by ¹H- and ¹³C-NMR spectroscopy that the 5-hydroxy-5-trichloromethyl-4,5-dihydro-1H-pyrazole intermediates 2a–j were formed quantitatively.     

Synthesis of 5-alkyl(aryl)sulfanyl-4-chloro-3-trichloromethyl-1,2-thiazoles and 5-Alkyl(aryl)sulfanyl-4-chloro-1,2-thiazole-3-carboxylic acids

Butane-, phenylmethane-, and benzenethiols reacted with 4,5-dichloro-3-trichloromethyl-1,2-thiazole in the presence of sodium ethoxide to give the corresponding 5-alkyl(aryl)sulfanyl-4-chloro-3-trichloromethyl-1,2-thiazoles. The reaction of 4,5-dichloro-1,2-thiazole-3-carboxylic acid with the same thiols under similar conditions resulted in the formation of sodium 4,5-dichloro-1,2-thiazole-3-carboxylate, while in the presence of pyridine 5-alkyl(aryl)sulfanyl-4-chloro-1,2-thiazole-3-carboxylic acids were obtained.     

Synthesis in Water and Antimicrobial Activity of 5-Trichloromethyl-4,5-dihydroisoxazoles

Two series of 5-trichloromethylisoxazoles were synthesized from the cyclocondensation of 1,1,1-trichloro-4-methoxy-3-alken-2-ones [Cl₃CC(O)C(R²) = C(R¹)OMe, where R¹ = H, Me, Et, Pr, iso-Pr, cyclo-Pr, Bu, terc-Bu, CH₂Br, CHBr₂, CH(Me)SMe, (CH₂)₂Ph, and Ph, and R² = H; R¹ = H and R² = Me and Et; R¹ and R² = -(CH₂)₄- and -(CH₂)₅-; and R¹ = Et and Ph and R² = Me] with hydroxylamine hydrochloride through a rapid one-pot reaction in water. The 5-trichloromethyl-4,5-dihydroisoxazoles were aromatized by reaction with concentrated sulfuric acid to obtain the respective 5-trichloromethylisoxazoles. Their structures were confirmed by elemental analysis, ¹H/¹³C nuclear magnetic resonance, and electron impact mass spectroscopy. Crystal structure analysis for 5-triclhoromethyl-5-hydroxy-3-propyl-4,5-dihydroisoxazole (2d) and 5-trichloromethyl-5-hydroxy-3,4-hexamethylene-4,5-dihydroisoxazole (2o) is presented. The antimicrobial activities of the 5-trichloromethyl-4,5-dihydroisoxazole derivatives were examined using the standard twofold dilution method against Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), and yeasts (Candida spp. and Cryptococcus neoformans). All of the tested 5-trichloromethyldihydroisoxazoles exhibited antibacterial and antifungal activities at the tested concentrations.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.     

Synthesis of 6-Alkyl Carbamato/Alkyl Thiocarbamato-2,10-dichloro-12-trichloromethyl-12 H -dibenzo[d,g][1,3,2]-dioxaphosphocin 6-Oxides

6-Alkylcarbamato/alkylthiocarbamato-2,10-dichloro-12-trichloromethyl-12 H -dibenzo [d,g][1,3,2]-dioxaphosphocin 6-oxides have been synthesized by the condensation of 2,2-bis(2-hydroxy-5-chlorophenyl)-1,1,1-trichloroethane with dichlorophosphinyl carbamates of different alcohols/thiols in the presence of triethylamine in dry toluene and were characterized by different spectral studies.     

Ethyl 5-trichloromethyl-1,2,4-oxadiazole-3-carboxylate as a versatile building block in medicinal chemistry

A straightforward route for preparing derivatives of ethyl 5-trichloromethyl-1,2,4-oxadiazole-3-carboxylate, in which the 5-trichloromethyl and/or the ester functionalities are displaced by various nucleophiles, has been designed. Mild reaction conditions were chosen to enable the formation of products, which constitute a new series of bifunctional 3,5-disubstituted 1,2,4-oxadiazole building blocks capable of being integrated into biologically relevant molecules.     

Trapping of reactive intermediates in dienone photochemistry by amines

Irradiation of 4-methyl-4-trichloromethyl-2,5-cyclohexadienones in amine solvents leads to the formation of the corresponding dichloromethyl cyclohexadienones by a process involving electron transfer from the amines to zwitterion intermediates.