Ozonolytic cleavage of cycloalkenes to terminally differentiated products

A method is described by which alkoxy hydroperoxides, obtained by ozonising cycloalkenes in alcohol solution, can be converted into terminally differentiated products by the action of metal salts. Cyclohexene and cycloheptene were converted to 1,1-dimethoxy-5-chloropentane and 1,1-dimethoxy-6-chlorohexane respectively in 47% yield, using ferric chloride. With ferrous sulphate as reactant salt, cyclooctene was converted into 1,1-dimethoxy-6-heptene. A synthesis of (Z)-4-heptenal from (Z,Z)-1,5-cyclooctadiene is also described. Fragmentation, causing the loss of one carbon atom, is a characteristic of these transformations. Other variations employed the salts as oxidants and reductants simultaneously.     

N-phosphorylated imidazolium salts as precursors to 2- and 5-phosphorylated imidazoles and new imidazol-2-ylidenes featuring the PNCN unit

It has been experimentally proven that the reaction of 1- or 1,2-disubstituted imidazoles with diorganylphosphorus(III) halides proceeds via initial formation of N-phosporylated imidazolium salts. Treatment of these salts with strong bases results in phosphorylation of the parent imidazoles at the 2- or 5-positions, correspondingly. In a previous case, imidazol-2-ylidenes are formed as intermediates. With both N1 and N3 atoms bearing sterically demanding or/and π-donating groups, deprotonation of 1,3-disubstituted imidazolium salts with NaN(SiMe(3))(2) afforded new stable N-phosphorus-substituted Arduengo-type carbenes.     

Pentafluorosulfanylnitramide salts

The synthesis and properties of a new class of inorganic salts, named pentafluorosulfanylnitramide salts (or pentafluorosulfanylnitraminic acid salts) [Z+SF5NNO2-], are described. A number of SF5-nitramide salts (Z+SF5NNO2-) were successfully prepared via nucleophilic displacements from carbamates and/or ion exchange techniques, but some salts [M(SF5NNO2)x; M = Li, Mg, Al] decomposed during isolation procedures and appear to be unstable in the solid state. Single-crystal X-ray diffraction was used to fully characterize the Z+SF5NNO2-, and their properties/structures are compared with those of the corresponding dinitramide salts (or dinitraminic acid salts), Z+N(NO2)2-. X-ray crystallography revealed major structural differences between N(NO2)2- and SF5N(NO2)- salts concerning the N-N distances and the angles subtended at the central nitrogen atom. In the N(NO2)2- salts, there are two nonequivalent N-N (average lengths 1.372(2) and 1.354(2) A) distances and an average N-N-N angle of 115.8(3) degrees (falls between sp3 and sp2 hybridization). In the SFsNNO2- salts, the average N-N distance is much shorter, 1.308(9) A, and the average N-N-S angle is 120.0(5) degrees (closely fits sp2 hybridization). The SF5NNO2- salts show a remarkable metrical similarity for the SF5 moiety in all structures, indicating a lack of sensitivity to its steric and electronic environment. This is in marked contrast to N(NO2)2-, where there is a wide variation in conformations adopted by these anions which can be related to their environment.     

Low-melting, low-viscous, hydrophobic ionic liquids: aliphatic quaternary ammonium salts with perfluoroalkyltrifluoroborates

A novel class of low-melting, hydrophobic ionic liquids based on relatively small aliphatic quaternary ammonium cations ([R(1)R(2)R(3)NR](+), wherein R(1), R(2), R(3) = CH(3) or C(2)H(5), R = n-C(3)H(7), n-C(4)H(9), CH(2)CH(2)OCH(3)) and perfluoroalkyltrifluoroborate anions ([R(F)BF(3)](-), R(F) = CF(3), C(2)F(5), n-C(3)F(7), n-C(4)F(9)) have been prepared and characterized. The important physicochemical and electrochemical properties of these salts, including melting point, glass transition, viscosity, density, ionic conductivity, thermal and electrochemical stability, have been determined and comparatively studied with those based on the corresponding [BF(4)](-) and [(CF(3)SO(2))(2)N](-) salts. The influence of the structure variation in the quaternary ammonium cation and perfluoroalkyltrifluoroborate ([R(F)BF(3)](-)) anion on the above physicochemical properties is discussed. Most of these salts are liquids at 25 degrees C and exhibit low viscosities (58-210 cP at 25 degrees C) and moderate conductivities (1.1-3.8 mS cm(-1)). The electrochemical windows of these salts are much larger than those of the corresponding 1,3-dialkyimidazolium salts. Additionally, a number of [R(F)BF(3)](-) salts exhibit plastic crystal behavior.     

Nucleophilic addition to substituted 1H-4,5-dihydroimidazolium salts

1H-4,5-Dihydroimidazolium salts 1 react readily with nucleophilic reagents originating cyclic products which may be stable or become transformed into acyclic compounds maintaining the structural ethylenediamine unit. With methylmagnesium iodide compound 1e affords the expected imidazolidine, but in the case of substituted 1-aryl-3-methyl-2-phenyl salts 1b-d the N-aryl-N′-methylethylenediamines 3b-d and acetophenone ( 4 ) were isolated, the process representing the transfer of the C-2 unit to a nucleophilic carbon. With alkaline cyanides salts 1 react efficiently affording α,α-diaminonitriles 5 . In these compounds the cyano group may be readily substituted by nucleophiles (hydroxyl anion, species with nucleophilic carbon and reagents that act by hydride ion transfer), in a way similar to the salts but with better yields.     

Hydride transfer from 1,4-dihydropyridines to pyridinium salts: Assessment of structural and energetic factors with hantzsch ester derived compounds

Hydride exchange occurs between 3,5 - di(alkoxycarbonyl) - 1,4 - dihydropyridines and their corresponding pyridinium salts. For the case of 1,2,6 - trimethyl - 3,5 - di(ethoxycarbonyl) - 1,4 - dihydropyridine in the presence of the structurally corresponding pyridinium perchlorate, hydride is transferred to the 4-position of the pyridinium salt in a reversible “blind” reaction as revealed by deuterium labeling experiments and to the 2,6-positions irreversibly to afford 1,2,6 - trimethyl - 3,5 - di(ethoxycarbonyl) - 1,2 - dihydropyridine as final product. Removal of the methyl groups at the 2,6-positions, i.e. 1 - methyl - 3,5 - di(methoxycarbonyl) - 1,4 -dihydropyridine and its structurally corresponding pyridium perchlorate, causes hydride transfer to become completely reversible. Substitution of the 4-position with Me, i.e. 1,2,4,6 - tetramethyl - 3,5 - di(methoxycarbonyl) -1,4- dihydropyridine and its corresponding pyridinium perchlorate leads to cessation of hydride transfer: the same is true for the analogous 4-phenyl (and substituted phenyl) compounds. However, these 1,4-dihydropyridines are capable of transferring hydride at reasonable temperatures to less highly substituted pyridinium salts. Activation parameters for some of these hydride transfers have been determined, mechanistic conclusions are presented, and the consequences of these observations for experiments with “model” NADH compounds are discussed.     

Preparation of new nitrogen-bridged heterocycles. 49. A new access to thieno[3,4-b]indolizine derivatives

The title compounds, together with 3-vinylindolizine-1-carbonitriles (4-56%), were prepared in 1-18% yields from the S-alkylation of pyridinium 1-[3-ethoxycarbonyl-1-[cyanomethylthio(thiocarbonyl)]]all ylides with alkyl halides, followed by treatment of the resulting pyridinium salts with a base and then a dehydrogenating agent. In several reactions of pyridinium salts obtained from reaction of the allylides with benzylic halides, trace amounts of bis[1-cyano-9-(ethoxycarbonyl)thieno[3,4-b]indolizin-3-yl] disulfides with an interesting superimposed structure were also isolated. The structures of these compounds were confirmed by X-ray analyses.     

Polychloride monoanions from [Cl3]- to [Cl9]- : a Raman spectroscopic and quantum chemical investigation

Polychloride monoanions stabilized by quaternary ammonium salts are investigated using Raman spectroscopy and state-of-the-art quantum-chemical calculations. A regular V-shaped pentachloride is characterized for the [N(Me)(4)][Cl(5)] salt, whereas a hockey-stick-like structure is tentatively assigned for [N(Et)(4)][Cl(2)???Cl(3)(-)]. Increasing the size of the cation to the quaternary ammonium salts [NPr(4)](+) and [NBu(4)](+) leads to the formation of the [Cl(3)](-) anion. The latter is found to be a pale yellow liquid at about 40 °C, whereas all the other compounds exist as powders. Further to these observations, the novel [Cl(9)](-) anion is characterized by low-temperature Raman spectroscopy in conjunction with quantum-chemical calculations.     

Mild route to generate gaseous metal anions

Gaseous metal anions such as Na(-), K(-), Cs(-), and Ag(-) can be generated at ambient temperatures by the collision-induced dissociation of the anions of several dicarboxylic acid salts, including oxalate, maleate, fumarate, succinate, and glutamate salts. The formation of gaseous metal anions in this way is unprecedented because the metal is initially present in its cationic form. The mild process described here could facilitate novel applications of metal anions as selective reagents for gas-phase ion-molecule and ion-ion reactions. Ab initio calculations were used to describe the dissociation process for anions of the oxalate salts. The formation of alkalides occurs via production of a metal-carbon dioxide anion intermediate with a bidentate three-center two-electron bond to the metal. The metal atom acquires a partial negative charge in the intermediate structure.     

Infrared and computational investigation of vanadium-substituted Keggin [PVnW12-nO40](n+3)- polyoxometallic anions

This study investigates complex salts of [PW(12)O(40)](3-), [PVW(11)O(40)](4-), [PV(2)W(10)O(40)](5-), and [PV(3)W(9)O(40)](6-) Keggin anions using Fourier transform infrared spectroscopy under ambient atmospheric and high-vacuum conditions and by computational methods. A detailed vibrational study suggests that the presence and amount of vanadium in these anions can be tested quickly and reliably with the help of infrared spectroscopy because the salts of these anions exhibit distinctly different infrared absorption signatures (particularly in the 1025-1250 cm(-1) region, where the P-O stretch is surrounded by a set of complex vibrations involving V-O and W-O bonds). Investigation of these salts with different countercations suggests that the overall appearance of the spectra, and thus the ability to use infrared as a diagnostic tool to identify the presence and number of vanadium atoms in Keggin structure anions, is not affected significantly. Last, it is shown that all the structures investigated are extremely stable across a wide range of temperatures.     

One-size adjustable-gap cluster anions: systematic approach to multinary, water-soluble chalcogenidometalate compounds

Reactions of defined mixtures of ternary salts [K 4(H 2O) 4][SnSe 4] and [K 4(H 2O) 0.5][SnTe 4] with transition-metal ions M = Zn (2+) or Mn (2+) provide an easy approach to penternary salts of quaternary cluster anions [M 4Sn 4Se 17- x Te x ] (10-), with x corresponding to the Se/Te ratio of the reactant mixture. In this way, it is possible to generate both protic solutions and single crystals with finely adjustable electronic excitation energies E g; the fact that the E g values cover the whole visible part of the electromagnetic spectrum as a function of the parameter x spotlights these cluster compounds with respect to diverse photocatalytic applications.     

A Simple Route to New N(3)-Substituted 5-Aryl-2-(dialkylamino)-1,3-oxazolium Salts and N(1)-Substituted 4-Aryl-2-(dialkylamino)-1H-imidazoles

In the reaction of N,N-dialkyl-dichloromethaniminium chlorides 11 with 2-aminoacetophenones 12 , a general and simple route to heretofore unknown 5-aryl-substituted 2-(dialkylamino)-1,3-oxazolium salts 13 and 5-aryl-substituted 2-(dialkylamino)oxazoles 14 was found. From the 2-(dialkylamino)-1,3-oxazoles 14 , the corresponding oxazolium salts 13 were obtained after alkylation with (MeO)₂SO₂. The new oxazolium salts 13 were converted to 1-substituted 4-aryl-2-(dialkylamino)-1H-imidazoles 9 by treatment with NH₄OAc. The possible use of these 1H-imidazoles as dye educts was explored. Analytical data, as well as AM1 calculations, reveal some remarkable differences between the structures of the neutral imidazoles 9 and their positively charged oxazolium precursors 13 .     

General synthetic route to benz[g]isoquinolines (2-azaanthracenes)

Benzylic zinc reagents add with high regioselectivity to 1-(phenoxycarbonyl) salts derived from pyridine-3-carboxaldehyde ( 1a ) or 3-acetylpyridine ( 1b ) to yield 1-(phenoxylcarbonyl)-4-benzyl-1,4-dihydropyridine-3-carboxaldehydes 5a, 5c or ketones 5b, 5d . Aromatizations of these dihydro analogues with sulfur led to the corresponding aldehydes 6a, 6c or ketones 6b, 6d . An alternate synthesis to the aldehydic precursors involved additions of benzylic zinc reagents to 1-(phenoxycarbonyl) salts formed from methyl nicotinates which led to the corresponding methyl 1-(phenoxycarbonyl)-4-benzyl-1,4-dihydronicotinates 7a, 7b . Aromatizations of 7a, 7b led to the corresponding pyridine esters 8a, 8b which on reduction with lithium aluminum hydride yielded the corresponding carbinols 9a, 9b . Oxidation of 9a, 9b by manganese dioxide afforded aldehydes 6e, 6f . Aldehydes 6a-f were readily converted into the benz[g]isoquinolines 10a-f on heating in polyphosphoric acid.     

Thermolysis of hydrogen sulphate,nitrate and perchlorate salts of diphenylamine. Part LXVIII

Hydrogen sulphate, nitrate and perchlorate salts of diphenylamine have been prepared and characterized by elemental, spectral and gravimetric analyses. Thermal decomposition of these salts has been evaluated by TG (static air) and DSC (inert atmosphere). The proton transfer reaction plays a major role during thermolysis of these salts. The diphenylammonium hydrogen sulphate under thermal and microwave irradiation forms 4-(phenylamino) benzenesulphonic acid by sulphonation process, whereas nitrate and perchlorate salts do not form corresponding nitro and perchloro derivatives, rather they ignite and explode, respectively, to form gaseous products along with a residual carbon .     

过渡金属吡啶配离子的TCNQ电荷转移盐的合成和物理性质

合成了通式为[M(Py)_m][TCNQ]_n(M=Mn,m＝4;M＝Co,Ni,Cu,m＝2;TCNQ＝7,7,8,8-四氰基对苯醌二甲烷,n＝2,3)的8个过渡金属吡啶配离子的TCNQ电荷转移盐,通过元素分析、红外光谱、顺磁共振谱、光电子能谱、磁化率和电导率对这些电荷转移盐进行了表征,结果表明,在这些电荷转移盐分子中存在TCNQ^-和TCNQ⁰,且TCNQ^-与TCNQ⁰相互作用形成结构单元[TCNQ]_n^2-(n＝2,3),各个结构单元沿一维方向堆积形成分子柱,部分电荷从[TCNQ]_n^2-向[M(Py)_m]²⁺转移,导致化合物中的金属表现为混合价态.其中3个电荷转移盐具有良好的导电性.     

Reaction of indolylpyrylium salts with some hydrazine derivatives

The reaction of 4-(3-indolyl)pyrylium salts with phenylhydrazine in alcohol gives 5-(3-indolyl)pyrazoles. The pyrylium salts react with acid hydrazides in refluxing dimethylformamide to give monohydrazones of the pseudobases of these salts (unsaturated 1,5-diketones).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 184–186, February, 1972.     

Cyclohexadienone diazeniumdiolates from nitric oxide addition to phenolates

Sterically hindered phenols react with nitric oxide under basic condititons to give either cyclohexadienone diazeniumdiolates or oximates. Phenols with 2,6-di-tert-butyl and 4-methyl (butylated hydroxy toluene, BHT), 4-ethyl, or 4-methoxy methylene substituents yield the corresponding 2,6-di-tert-butyl-2, 5-cyclohexadienone-4-alkyl-4-diazeniumdiolate salts (4-methyl 1a, 4-ethyl 3a, 4-methoxymethylene 5a). Phenols with 2,6-di-tert-butyl and 4-methylene (2,6-di-tert-butylphenol) substituents yield 4-methoxymethylenediazeniumdiolate (5a) together with 2, 6-di-tert-butyl benzoquinone oximate (6a), while phenols with 2, 6-di-tert-butyl and 4-methylenedimethylamino or hydrogen substituents yield exclusively 2,6-di-tert-butyl benzoquinone oximate (6a). Alkylation of the silver salts of 1a, or treating the O(2)-protonated diazeniumdiolate with diazomethane, both yield mixtures of O(1)- and O(2)-methylated isomers. All the compounds exhibit exothermic thermal decomposition except the quinuclidinium (1e, 3e, 5e) and triethylenediammonium (1f) salts which decompose endothermically. Three of the compounds namely "O(2)-protonated" (Z)-1-[4-(2, 6-di-tert-butyl-4-methyl-cyclohexadienonyl)]diazen-1-ium+ ++-1, 2-diolinic acid (1b), O(2)-methyl (Z)-1-[4-(2, 6-di-tert-butyl-4-methyl-cyclohexadienonyl)]diazen-1-ium+ ++-1,2-diolate (1c), and "O(2)-protonated" (Z)-1-[4-(2, 6-di-tert-butyl-4-methoxymethylenecyclohexadienonyl)]diazen- 1-ium-1, 2-diolinic acid (5b) were characterized by single-crystal X-ray diffraction studies. The diazeniumdiolate framework in all the structures is coplanar with considerable pi-bonding delocalized over the O-N-N-O framework.     

Reaction of aldimine anions with vinamidinium chloride: three-component access to 3-alkylpyridines and 3-alkylpyridinium salts and access to 2-alkyl glutaconaldehyde derivatives

N-tert-Butylimino derivatives of aldehydes were deprotonated with LDA and reacted with vinamidinium chloride to give 2-alkylaminopentadienimine derivatives, which were isolated as their corresponding hydrochloride in 68-81% yield. Reaction of these derivatives with ammonium acetate or salts of primary amines, in n-butanol at 80 degrees C, afforded the corresponding 3-alkylpyridines or 3-alkylpyridinium salts in high yield. Alkaline hydrolysis of 2-alkylaminopentadieneimine derivatives allowed a practical accesss to potassium salts of 2-alkylglutaconaldehyde.     

Approach to the synthesis of indoline derivatives from diaryliodonium salts

An effective method of constructing the indoline moiety via intramolecular nucleophilic ring closure of a diaryliodonium salt is described. Diacetoxyiodoarene compounds (1a-1e) were converted into intermediate Koser's reagent and coupled with arylstannanes (7-10) to form diaryliodonium salts (11a-14e). Indoline compounds with different N-protecting groups, 15, 16, 17, and 18, were synthesized in higher yields by treating salts (11a-14e) with Cs(2)CO(3) and TEMPO. Regardless of the electronic environment of five para-substituted iodoarenes and the natures of four N-protected arylstannane groups, the conversion proceeded well to afford corresponding indolines in yields of 72-84 and 70-84%, respectively.     

Synthesis and structural studies of 1,1'-bis-amino-functionalized ferrocenes, ferrocene salts, and ferrocenium salts

Having isolated and characterized a series of sodium cyclopentadienide salts, we have synthesized a number of 1,1'-bis-amino-functionalized ferrocenes, 1,1'-bis-amino-functionalized ferrocene salts, and 1,1'-bis-amino-functionalized ferrocenium salts. Among these are the first crystallographically characterized examples of cyclopentadienyl units containing (piperidin-N-ylethyl)- and (pyrid-2-ylmethyl)cyclopentadienyl side chains. In the cases of some of the ferrocenes, ferrocene salts, and ferrocenium salts, there are some interesting structural features in the solid state. These include C-H...N and C-H...pi cloud interactions as well as N-H...O and N-H...F hydrogen bonds.