The preparation of heterocyclic materials from 2-isocyanatobenzoyl chloride and difunctional nucleophiles

2-Isocyanatobenzoyl chloride was treated with difunctional nucleophiles such as o-phenylenediamine, 1,8-diaminonaphthalene, o-aminothiophenol, and thioacetamide. The diaminonucleophiles gave intermediates which were thermally cyclized, and the other nucleophilic reagents gave heterocyclic materials directly.     

Reactions of trifluoroacetyl isocyanate with arylsulfamides

The reaction of trifluoroacetyl isocyanate with arylsulfamides gives N-trifluoroacetyl-N -arylsulfonylureas and 1-arylsulfonyl-1,3,5-triazine-2,4,6(1H,3H,5H)-triones in 10–15% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2151–2153, September, 1990.     

The tautomerism of 5-aminotetrazole

In the reaction of 5-amino-1-methyltetrazole and 5-amino-2-methyltetrazole with carboxylic acid anhydrides or chlorides, diacylamides are obtained in addition to monoacyl derivatives. The results of independent synthesis and a study of IR and PMR spectra have shown that in the diacylamides considered both acyl groups are attached to the same (the exocyclic) nitrogen atom.For part VI, see [1].     

On the tautomerism of 5-aminotetrazole

In order to study the connection between the structure of sulfanilamides and their antibacterial action, sulfanilamide derivatives of 1- and 2-methyl-5-aminotetrazoles and of 1,3-dimethyl-5-iminotetrazole have been synthesized. A study of their IR spectra has shown that 1-methyl-5-sulfanilimidotetrazole has the imide structure in the crystalline state and 2-methyl-5-sulfanilamidotetrazole the amide structure. The sulfanilamide derivatives of 1- and 2-methyl-5-aminotetrazoles possess a considerable antibacterial activity, while 1, 3-dimethyl-5-sulfanilimidotetrazole is inactive.For communication V, see [1].     

A vibrational spectroscopic study of 1-methyl and 2-methyl-5-aminotetrazole

The infrared spectra of 1-methyl and 2-methyl-5-aminotetrazole have been measured from 4000 to 180 cm⁻¹: polarized spectra have also been obtaine     

On the tautomerism of 5-aminotetrazole

In order to study the connection between the structure of sulfanilamides and their antibacterial action, sulfanilamide derivatives of 1- and 2-methyl-5-aminotetrazoles and of 1,3-dimethyl-5-iminotetrazole have been synthesized. A study of their IR spectra has shown that 1-methyl-5-sulfanilimidotetrazole has the imide structure in the crystalline state and 2-methyl-5-sulfanilamidotetrazole the amide structure. The sulfanilamide derivatives of 1- and 2-methyl-5-aminotetrazoles possess a considerable antibacterial activity, while 1, 3-dimethyl-5-sulfanilimidotetrazole is inactive.     

Reactions of 1,2,2,2-tetrachloroethyl isocyanate with trialkyl and trimethylsilyl phosphites

The reaction of 1,2,2,2-tetrachloroethyl isocyanate with trialkyl phosphites is unselective. It involves chlorine substitution, addition by the isocyanate group, and dehydrochlorination and gives rise to a mixture of mono- and diphosphorylated compounds. Diethyl trimethylsilyl phosphite more selectively reacts with 1,2,2,2-tetrachloroethyl isocyanate. At a 1:1 molar reagent ratio, an -phosphorylated trichloroethyl isocyanate is formed, and at a 2 : 1 ratio, chlorine substitution and addition by the isocyanate group take place to give a related 1,3-diphosphonate.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 9, 2004, pp. 1456–1459.Original Russian Text Copyright © 2004 by Onysko, Maidanovich, Sinitsa.This revised version was published online in April 2005 with a corrected cover date.     

Thermal analysis of laser-controlled 5-aminotetrazole propellant

Resorting to the continuous assistance of external laser radiation, laser augmented chemical propulsion (LACP) reveals superior combustion performance. However, the corresponding combustion theories have still to be ascertained for this innovative propulsion technique. Thermal characteristics of 5-aminotetrazole (5-ATZ) propellant are studied for LACP. In nitrogen environment, unique structures of burning surface are formed under laser ablation in bare samples of 5-ATZ propellant pressed powders. Resorting to an outer tube, a thermocouple is inserted in 5-ATZ propellant samples to obtain the temperature trace during combustion. In analogy with the burning surface structure reconstructed by micro computed tomography (MicroCT), the temperatures values of three significant regions were obtained. The experimental dependences of the measured temperatures on environment pressure and laser power are discussed.     

Reactions of 1,4-dioxa-2-silacyclohexanes with acetyl chloride

The reactions of 1,4-dioxa-2-silacyclohexanes with acetyl chloride lead to the cleavage of the Si−O bond to form chlorotriorganosilanes containing the acetoxy group in the organic radical at the silicon atom. Hydrolysis of these chlorosilanes affords bis(acetoxy-alkoxy(aryloxy)methyl)disiloxanes, while the reactions with cage copper sodium phenylsiloxane give dodecaphenyl[dodeca(acetoxyorganodimethylsilyloxy)]cyclododecasiloxanes. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2527–2529, December, 1998.     

Reactions of 1,3,3,3-tetrafluoro-2-methoxycarbonylpropenesulfenyl chloride with enamines

1,3,3,3-Tetrafluoro-2-methoxycarbonylpropenesulfenyl chloride readily reacts with enamines (derivatives of -oxo acids) to give sulfenylation products. The reactions with N-aryl-substituted enamines are accompanied by cyclization to form N-aryl-2-(2,2,2-trifluoro-1-methoxycarbonylethylidene)-2,3-dihydrothiazoles.     

Reactions of methylenecyclopropanes with phenylsulfenyl chloride and phenylselenyl chloride

The reaction of methylenecyclopropanes 1 with phenylsulfenyl chloride or phenylselenyl chloride gives (cyclobut-1-enylsulfanyl)benzene or (cyclobut-1-enylselanyl)benzene along with ring-opened product in good total yields at 0 degrees C in various solvents. A plausible mechanism has been proposed.     

Reactions of derivatives of anthranilic acid with 3-chloropropyl isocyanate

The urea 1 obtained from anthranilonitrile and 3-chloropropyl isocyanate is converted into 3-(3-chloropropyl)-2,4(1H,3H)quinazolinedione ( 4 ) when heated with hydrochloric acid, whereas it undergoes a double cyclization to form 2,3,4,7-tetrahydro-6H-pyrimido[1,2-c]quinazolin-6-one ( 3 ) upon heating, or treatment with ammonia. On the other hand, the urea 5 formed from methyl anthranilate and 3-chloropropyl isocyanate cyclizes in three different ways, when treated with ammonia, potassium bicarbonate, or concentrated sulfuric acid, to yield compound 4 , 3,4-dihydro-2H,6H-[1,3]oxazino[2,3-b]quinazolin-6-one ( 9 ), or 2-[(3-chloropropyl)amino]-4H-3,1-benzoxazin-4-one ( 6 ), respectively. Acid-catalyzed reactions of compound 9 with nucleophilic reagents proceed with opening of the oxazine ring and readily yield various 3-substituted 2,4(1H,3H)-quinazolinediones.     

Sulfonylcarbamimidic azides from sulfonyl chlorides and 5-aminotetrazole

Treatment of o-nitrobenzenesulfonyl chloride ( 3 ) with 5-aminotetrazole (5-AT) gave [(2-nitrophenyl)-sulfonyl]carbamimidic azide ( 6 ), a ring-opened isomer of the expected N-(1H-tetrazol-5-yl)-2-nitrobenzenesulfonamide ( 4 ). Sulfonylcarbamimidic azide 6 was converted to 2-amino-N-(aminoiminomethyl)benzene-sulfonamide ( 7 ) with ethanolic stannous chloride, and to 3-amino-1,2,4-thiadiazine 1,1-dioxide ( 8 ) with sodium dithionite. Methanesulfonyl chloride ( 9 ) and 5-AT gave 2-(methylsulfonyl)carbamimidic azide ( 10 ), which isomerized to 5-[(methylsulfonyl)amino]-1H-tetrazole ( 11 ) in warm ethanol. Attempted cycloaddition of 2-(phenylsulfonyl)carbamimidic azide ( 13 ) and ethyl vinyl ether led only to alkylated tetrazole products. In addition, other tetrazole-alkylating reactions are described. Isomers produced from these alkylations were differentiated with ¹³C nmr spectroscopy.     

Reactions of 2-aryl-4-arylidene-4<Emphasis Type="Italic">H</Emphasis>-oxazol-5-ones with 3-amino-1,2,4-triazole, 5-aminotetrazole,and 2-aminobenzimidazole

The reactions of 3-amino-1,2,4-triazole, 5-aminotetrazole, and 2-aminobenzimidazole with 2-aryl-4-arylidene-4H-oxazol-5-ones (azlactones) were studied. The electron-releasing properties of the azole ring were demonstrated to influence the reaction pathway of azlactones with aminoazoles. The structures of the resulting compounds were established by ¹H and ¹³C NMR spectroscopy using spin-spin decoupling and the nuclear Overhauser effect.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2730–2733, December, 2004.     

Reactions of 1,3,3,3-tetrafluoro-2-methoxycarbonylpropenylsulfenyl chloride with aromatic and heterocyclic compounds

1,3,3,3-Tetrafluoro-2-methoxycarbonylpropenylsulfenyl chloride readily reacts with activated aromatic and heterocyclic compounds to form C-sulfenylation products as Å isomers. In some cases, its reactions with phenolic compounds are accompanied by cyclization giving rise to fused 2-(2,2,2-trifluoro-1-methoxycarbonylethylidene)-1,3-oxathioles.     

Reactions of salicylamides with thionyl chloride

A series of compounds having the 1,2,3-benzoxathiazin-4 (3H) one 2-oxide structure have been synthesized by the interaction of thionyl chloride with the appropriate salicylamide. Some properties of these compounds as well as some by-products are described.     

Mechanism and kinetics of the thermal decomposition of 5-aminotetrazole

The kinetics of 5-aminotetrazole thermal decomposition in the condensed phase at high heating rates (∼100 K/s) was studied by the dynamic mass spectrometric thermal analysis using a molecular beam sampling system, and the product composition was determined. Two routes of 5-aminotetrazole decomposition were distinguished, one yielding HN₃ and NH₂CN (route 1), and the other N₂ and CH₃N₃ (route 2). The activation energy and rate constant of 5-AT decomposition were determined for each route.     

Reactions of indolylmagnesium bromide with trans-2-phenylcyclopropane-1-carbonyl chloride

Russian Journal of General Chemistry -