Synthesis and reactions of a monosubstituted dithiirane 1-oxide, 3-(9-triptycyl)dithiirane 1-oxide

A 3-monosubstituted dithiirane 1-oxide, 3-(9-triptycyl)dithiirane 1-oxide, was prepared for the first time, by the reaction of (9-triptycyl)diazomethane and S₈O. The dithiirane 1-oxide was obtained as cis- and trans-isomers, and the structure of the trans-isomer was verified by X-ray crystallography. The cis-isomer isomerized gradually to the trans-isomer in solution. The divalent sulfur atom of the cis- and trans-dithiirane 1-oxides were removed on treatment with triphenylphosphine to give the corresponding Z- and E-sulfines, respectively. The reaction of the trans-dithiirane 1-oxide with (Ph₃P)₂Pt(C₂H₄) provided the (sulfenato-thiolato)Pt^II complex, and that with Lawesson's reagent yielded the 1,3,4,2-trithiaphospholane and 1,2,4,5,3-tetrathiaphosphorinane derivatives.     

Electrophilic reactions of 3-hydroxyquinoline-1-oxide

Conclusions A synthesis is described for 3-hydroxyquinoline-1-oxide. The aminomethylation and halogenation reactions of this compound proceed at C-4 in the quinoline ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1660–1662, July, 1984.     

Acylation of 1-methoxy-3-methyl-1-triazene 2-oxide

Chlorides and anhydrides of carboxylic (including dicarboxylic) acids react with salts of 1-methoxy-3-methyl-1-triazene 2-oxides to give the corresponding 3-acyl-1-methoxy-3-methyl-1-triazene 2-oxides.     

Preparation of 3(5)-phenyl-1-hydroxypyrazole 2-oxide and 4-methyl-3(5)-phenyl-1-hydroxypyrazole 2-oxide

Nitrosation of acrylophenone oxime or of methacrylophenone oxime with n-butyl nitrite in the presence of pyridine and copper(II) sulfate gives the copper complexes of the title compounds. The free 1-hydroxypyrazole 2 -oxides are isolated by treating the copper complexes with dilute sodium hydroxide, filtration, and acidification of the basic filtrates. The title compounds are the first examples of 1-hydroxypyrazole 2 -oxides in which the C3(5) ring position is unsubstituted.     

Synthesis, structure, and reactions of 1-tert-butyl-2-diphenylphosphino-imidazole

Metalation reactions were studied of a sterically demanding imidazole derivative, namely, 1-tert-butylimidazole (1), with different metalation reagents and subsequent reaction with diphenylchlorophosphane. The reaction product, 1-tert-butyl-2-diphenylphosphino-imidazole (2), was subjected to oxidation and complexation reactions to yield the corresponding products Ph(2)(Imi)P-E (E = O (3), S (4), Se (5), W(CO)(5) (8)) and in the case of borane-THF the N-BH(3) coordination product 10 was obtained. The analytical data of the new compounds are discussed, including X-ray diffraction studies of 3-5.     

Synthesis and reactions of some substituted 1, 3, 5-triazines

The reactions of 2-substituted 4, 6-dihydroxytriazines with PCl₅ and SOCl₂ are investigated. It is shown that conversion of 2-(aryl- and substituted styryl)-4, 6-dihydroxy-1, 3, 5-triazine to the corresponding 4, 6-dichloro compounds is accompanied by ring opening and, in the case of styryl derivatives, by chlorination of the ethylene group. Analysis of the IR spectra of 4, 6-dihydroxytriazines establishes that under ordinary conditions they are 4, 6-dihydroxytetrahydrotriazines. Shift of the lactim-lactam equilibrium towards the oxo form is considered to be the reason why these compounds react with difficulty with SOCl₂. A mechanism for the reaction of triazine hydroxy derivatives with PCl₅ is put forward. New substituted triazines and intermediates are synthesized.     

Pummerer-type reactions in the (2-methylsulfanyl-2-phosphonyl) thiopyran 1-oxide series

Two (3,6-dihydro-2-methylsulfanyl-2H-thiapyran-2-yl)phosphonate derivatives have been chemoselectively oxidized on the thiopyran sulfur. The obtained allylic six-membered cyclic sulfoxides 2a and 2b were reacted under Pummerer reaction conditions leading to new thiopyran derivatives (4a and 6b, respectively). In both studied cases, the nucleophilic attack of β,γ-unsaturated thionium ion intermediate took place regioselectively at the γ-position (even when occupied by a methyl substituent like in 2b). An unexpected second product 7b was however obtained from substrate 2b (having the dimethyl-substituted double bond). Dephosphorylation of 7b under basic conditions led to an original conjugated tri-unsaturated trifluromethylcarbonyl thiopyran product (8b). These results represent new original examples of the Pummerer reaction.     

Synthesis and reactions of 1-methyl-3-formylindazole

It is shown that oxidation of 1-methyl-3-hydroxymethylenediazole with a solution of potassium dichromate in dilute sulfuric acid gives a 30% yield of 1-methyl-3-formylindazole. Condensation products of the latter with malonic acid, nitromethane acetophenone, hippuric acid, hydantoin, thiohydantoin, and rhodanine are obtained. An oxime and a semicarbazone are prepared.     

Alkylation of 1-alkoxy-3-methyl-1-triazene 2-oxide sodium salts

1-Alkoxy-3-methyl-1-triazene 2-oxide sodium salts react with chloromethyl methyl sulfide to give a mixture of 1-alkoxy-3-methyl-3-(methylthiomethyl)-1-triazene 2-oxides and 3-alkoxy-1-methyl-3-(methylthiomethyl)-1-triazene 2-oxides. The reaction of these triazene oxide sodium salts with 3,3-dialkyl-1-chloromethoxy-1-triazene 2-oxides produces a complex mixture of product bearing the oxytriazene moieties of the starting alkoxy-1-triazene 2-oxides bonded with the methylene group as a key structural fragment.     

Photochemistry of 1-methoxyphthalazine 3-oxide

Irradiation of 1-methoxyphthalazine 3-oxide in cyclohexane at 3500 Å resulted in the formation of phthalimide. On the other hand, irradiation in the presence of maleic anhydride resulted in the formation of 1-methoxynaphthalene-2,3-dicarboxylic acid anhydride. The similar cycloadduct was also observed by irradiation in the presence of benzoquinone. The formation of the cycloaddition products was also observed in acetic anhydride at 60°.     

Synthesis and thermal reactions of 3-trimethylsilyl-1-pyrazoline

The compound 3-trimethylsilyl-1-pyrazoline has been synthesized by addition of diazomethane to vinyltrimethylsilane at room temperature. In contrast, addition of trimethylsilyldiazomethane to ethylene at 55°C yields 1-trimethylsilyl-2-pyrazoline exclusively. The thermal isomerization of 3-trimethylsilyl-1-pyrazoline to 1-trimethylsilyl-2-pyrazoline has been followed kinetically by proton NMR spectroscopy and the reverse reaction has been detected by gas phase pyrolysis. Thermal elimination of nitrogen from either pyrazoline leads to cyclopropyltrimethylsilane, allyltrimethylsilane and E- and Z-1-propenyltrimethylsilane. The relative rates of methylene-H migration to radical centers α and γ to silicon are approximately equal.     

2-(3’,5’-二硝基苯)-4-硝基-1,2,3-三唑-1-氧化物的合成与量子化学研究

以乙二醛、苯肼和盐酸羟胺为起始原料,经缩合和肟化反应制得肟基苯腙(1)。在硫酸铜-吡啶-水体系中,1经缩合环化得2-苯基-1,2,3-三唑-1-氧化物(2);2被混酸硝化合成了新化合物2-(3’,5’-二硝基苯)-4-硝基-1,2,3-三唑-1-氧化物(3),纯度99%,总收率45%,其结构经1H NMR,IR,MS和元素分析表征。在B3LYP/aug-cc-pVDZ基组水平上对3的结构进行了优化,获得稳定的几何构型。     

Synthesis of 2-methoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide, A New Potential Antitumor Phosphorus Heterocycle Compound

The discoveries that the bisdioxopiperazines ICal- 154', ICal-- 159(razoxane)' and MST16(sobuzoxan)' are inhibitors of mammalian DNA topoisomerase II'-', have led to arenewed interest in these compounds as antitumor agents'. Among the drugs, MST-16(sobuzoxan) was approved in Japan (in 1994) as a potent antit'Umor agent for treatmentof adult T-cell leukemia and malignant lymphoma'. However, the bisdioxopiperazinesexhibited extremely small water-solubility, which reduced its absorption in…