Search

WstępNastrój jest aspektem temperamentu związanym ze stopniem wrażliwości i kierunkiem odpowiedzi emocjonalnej danej osoby, a znacznie mniej z wpływem wydarzeń życiowych. Jednak niepełnosprawność dziecka i opieka nad nim niewątpliwie znajduje odbicie w nastroju jego rodziców.CelCelem niniejszych badań był opis nastroju, jakiego doświadczają rodzice dzieci jąkających się, przy uwzględnieniu czynników związanych z niepełnosprawnością dziecka, a tym samym poznanie wycinka specyfiki funkcjonowania rodziny z dzieckiem jąkającym się.Materiał i metodyW badaniu zastosowano Przymiotnikową Skalę Nastroju G. Matthewsa, A. Chamberlaina, D. M. Jonesa, Kwestionariusz Samopoczucia D. Mc Naira, M. Lorra i L. Dropplemana, Skalę Samooceny i Oceny Jąkania Z. Tarkowskiego i J. Góral-Półroli oraz ankietę osobową. Badaniami objętych zostało 61 rodziców, wychowujących dzieci w wieku od 7 do 15 lat z diagnozą niepłynności mówienia.WynikiAnaliza wyników pokazała, że u badanych rodziców dzieci jąkających się dominuje nastrój negatywny oraz rozemocjonowanie. Zmienne dotyczące głębokości jąkania częściowo różnicują nastrój odczuwany przez badanych rodziców.WnioskiPrzeprowadzone badania pokazują, iż jąkanie u dziecka może być przyczyną wielu konfliktów i problemów emocjonalnych rodziców, jednocześnie wskazują obszary, w których rodzicom dzieci jąkających się należałoby udzielić wsparcia.

The hetero-Diels-Alder reactions of in situ-generated azoalkenes with thioketones were shown to offer a straightforward method for an efficient and regioselective synthesis of scarcely known N-substituted 1,3,4-thiadiazine derivatives. The scope of the method was fairly broad, allowing the use of a series of aryl-, ferrocenyl-, and alkyl-substituted thioketones. However, in the case of N-tosyl-substituted cycloadducts derived from 1-thioxo-2,2,4,4-tetramethylcyclobutan-3-one and the structurally analogous 1,3-dithione, a more complicated pathway was observed. By elimination of toluene sulfinic acid, the initially formed cycloadducts afforded 2H-1,3,4-thiadiazines as final products. Advanced DFT calculations revealed that the observed high regioselectivity was due to kinetic reaction control and that the (4 + 2)-cycloadditions of sterically less unhindered thiones occurred via highly unsymmetric transition states with shorter C..S-distances (2.27–2.58 Å) and longer N..C-distances (3.02–3.57 Å). In the extreme case of the sterically very hindered 2,2,4,4-tetramethylcyclobutan-1,3-dione-derived thioketones, a zwitterionic intermediate with a fully formed C‒S bond was detected, which underwent ring closure to the 1,3,4-thiadiazine derivative in a second step. For the hypothetical formation of the regioisomeric 1,2,3-thiadiazine derivatives, the DFT calculations proposed more symmetric transition states with considerably higher energies.

The influence of microwave and ultrasonic irradiation on the performance of ammonium-tagged Ru-based catalysts in olefin metathesis transformations in aqueous media was studied. Differences in the catalytic activity in correlation with the nature of the present counter ion and the size of the N-heterocyclic carbene (NHC) ligand were revealed. The presented methodology allows for preparation of a variety of polar and non-polar metathesis products under environmentally friendly conditions.

Differently substituted hetaryl thioketones react with less reactive diazoketones under microwave (MW) irradiation in toluene solution. After only 2 min, the reactions were complete and, depending ...

The in situ generated nitrilimines are trapped efficiently with heteroaryl thioketones bearing thiophen-2-yl or selenophen-2-yl substituents. The exclusive products observed in these reactions are 2,3-dihydro-1,3,4-thiadiazoles formed via regioselective [3+2]-cycloaddition. Competitive head-to-tail dimerization of the intermediate 1,3-dipoles was not observed in any of the studied reactions.

Hydrogen sulfide is a toxic gas involved in the regulation of some essential biological processes. A novel, precise, accurate and rapid method based on high-performance liquid chromatography with diode array detection for the determination of sulfide ions in human urine sample is proposed. The method involves the derivatization of sulfide with pyrylium salts – (2,4,6-triphenylpyrylium hydrogensulfate(VI) (L1) and 4-[p-(N,N-dimethylamino)phenyl]-2,6-diphenylpyrylium chlorate(VII) (LN1). The separation occurs on InfinityLab Poroshell 120 EC C18 column using acetonitrile and phosphate buffer as a mobile phase. The detectors utilized a wavelength of 371 or 580 nm. The calibration curves were linear in the range of 2–150 μmol L−1 and 1–50 μmol L−1 for L1 and LN1 derivatives, respectively. The samples were found to be stable from sample collection to final analysis. The method was successfully applied to samples from apparently healthy volunteers.

&lsquo, Desymmetrization&rsquo, of trans-1,2-diaminocyclohexane by treatment with &alpha, &omega, dihalogenated alkylation reagents leads to mono-NH2 derivatives (&lsquo, primary-tertiary diamines&rsquo, ). Upon reaction with formaldehyde, these products formed monomeric formaldimines. Subsequently, reactions of the formaldimines with &alpha, hydroxyiminoketones led to the corresponding 2-unsubstituted imidazole N-oxide derivatives, which were used here as new substrates for the in situ generation of chiral imidazol-2-ylidenes. Upon O-selective benzylation, new chiral imidazolium salts were obtained, which were deprotonated by treatment with triethylamine in the presence of elemental sulfur. Under these conditions, the intermediate imidazol-2-ylidenes were trapped by elemental sulfur, yielding the corresponding chiral non-enolizable imidazole-2-thiones in good yields. Analogous reaction sequences, starting with imidazole N-oxides derived from enantiopure primary amines, amino alcohols, and amino acids, leading to the corresponding 3-alkoxyimidazole-2-thiones were also studied.

‘Desymmetrization’ of trans-1,2-diaminocyclohexane by treatment with α,ω-dihalogenated alkylation reagents leads to mono-NH2 derivatives (‘primary-tertiary diamines’). Upon reaction with formaldehyde, these products formed monomeric formaldimines. Subsequently, reactions of the formaldimines with α-hydroxyiminoketones led to the corresponding 2-unsubstituted imidazole N-oxide derivatives, which were used here as new substrates for the in situ generation of chiral imidazol-2-ylidenes. Upon O-selective benzylation, new chiral imidazolium salts were obtained, which were deprotonated by treatment with triethylamine in the presence of elemental sulfur. Under these conditions, the intermediate imidazol-2-ylidenes were trapped by elemental sulfur, yielding the corresponding chiral non-enolizable imidazole-2-thiones in good yields. Analogous reaction sequences, starting with imidazole N-oxides derived from enantiopure primary amines, amino alcohols, and amino acids, leading to the corresponding 3-alkoxyimidazole-2-thiones were also studied.

A series of hydrazonoyl bromides prepared from readily available N-arylhydrazones of fluoral was used for the in situ generation of fluorinated nitrile imines. These 1,3-dipoles were efficiently trapped with aryl and hetaryl thioketones yielding fluoromethylated 2,3-dihydro-1,3,4-thiadiazoles. The [3+2]-cycloadditions occurred with complete regioselectivity yielding the respective products in high yields. Reactions proceeded with remarkable tolerance to functional groups, and the corresponding N(3)-aryl derivatives bearing halogens, methoxy, benzoyloxy, methoxycarbonyl, and nitrile substituents at the para position of the phenyl ring were prepared as crystalline products. Spectroscopic data (13C and 19F NMR) of the obtained [3+2]-cycloadducts evidenced remarkable relationship between the shielding effect of the CF3 group and the electronic properties of the para-substituents.

A series of hockey-stick shaped 6-oxoverdazyl radicals 1[n]–3[n], containing CH3 (a), CF3 (b) and CN (c) groups in the short ‘arm’, were prepared and their physical properties were investigated. Mesogenic behaviour was found only in the CN derivatives with the COO (1[n]c) and N=N (2[12]c) linking groups, which exhibited a nematic phase. Analysis of binary mixtures of selected compounds with bent-core nematic host 4[12] gave virtual nematic-isotropic transition temperatures, [TNI], which follow the order 1[12]b

Methods for the synthesis of hetaryl and ferrocenyl thioketones as well as applications of this class of organic sulfur compounds in the synthesis of both sulfur-containing and sulfur-free organic products are summarized. The most important applications relate to [2+2]-, [3+2]-, and [4+2]-cycloadditions. Aromatic thioketones react with diazomethane at −70°C, and the formed 1,3,4-thiadiazolines can be used as convenient precursors of reactive thiocarbonyl S-methanides. In contrast, the hetaryl thioketones do not form this type of cycloadducts. Reactions of hetaryl thioketones with thiocarbonyl S-methanides are proposed to occur via a stepwise diradical mechanism. Aryl and hetaryl thioketones react as prone heterodienophiles with cyclic and acyclic dienes. The first asymmetric synthesis of dihydrothiopyranes from aryl and hetaryl thioketones was performed using a L-proline-derived organocatalyst. Hetaryl thiochalcones are useful heterodienes for the preparation of hetaryl-substituted dihydrothiopyrans.

Ferrocenyl thioketones bearing a hetaryl, phenyl or alkyl group as the second substituent react with (trimethylsilyl)diazomethane at ca. −30°C in THF solution without formation of a stable [3 + 2]-...

The reactions of aryl (selenophen-2-yl) thioketones with CH2N2 occur with spontaneous elimination of N2, even at low temperature (−65°), to give regioselectively sterically crowded 4,4,5,5-tetrasubstituted 1,3-dithiolanes and/or a novel type of twelve-membered dithia-diselena heterocycles as dimers of the transient thiocarbonyl S-methanides. The ratio of these products depends on the type of substituent located at C(4) of the phenyl ring. Whereas the formation of the 1,3-dithiolanes corresponds to a [3+2] cycloaddition of an intermediate thiocarbonyl ylide with the starting thioketone, the twelve-memberd ring has to be formed via dimerization of the ‘thiocarbonyl ylide’ with an extended biradical structure.

A series of phenyl/hetaryl and bishetaryl thioketones have been prepared via oxygen/sulfur exchange of the corresponding ketones by treatment with Lawesson’s reagent. The nonsymmetrical ketones were conveniently accessible via the reactions of lithiated furan, thiophene, and selenophene with N,N-dimethylbenzamide and hetarylcarboxamides, respectively, whereas the symmetrical ketones were obtained by treatment of ethyl N,N-dimethylcarbamate with 2 equiv of lithiated heterocycles. Under typical conditions, selected examples of the hetaryl thioketones were oxidized selectively to give thiocarbonyl S-oxides (sulfines). Reactions with diazomethane at –65°C yielded 1,3-dithiolanes in a regioselective manner and hetero-Diels–Alder reactions of 2-thienyl substituted thioketones with dimethyl acetylenedicarboxylate yielded the corresponding 7H-thieno[2,3- c]thiopyran-4,5-dicarboxylates.

An intriguing stepwise diradical mechanism of the dimerization of the reactive intermediate (thiocarbonyl S-methanide) appearing in the reaction of phenyl selenophen-2-yl thioketone with diazomethane was studied by means of computational methods. The preferred formation of the unusual macroheterocycle, competitive with the 1,3-ring closure leading to a thiirane and the head-to-head dimerization yielding a 1,4-dithiane derivative, respectively, was explained based on the analysis of the structure of the favored conformer of the intermediate, delocalized diradical species. The influence of selenium as a ‘heavy atom’ for stabilization of this intermediate has been emphasized.

The thermal reaction of trans-1-methyl-2,3-diphenylaziridine (trans-1a) with aromatic and cycloaliphatic thioketones 2 in boiling toluene yielded the corresponding cis-2,4-diphenyl-1,3-thiazolidines cis-4via conrotatory ring opening of trans-1a and a concerted [2+3]-cycloaddition of the intermediate (E,E)-configured azomethine ylide 3a (Scheme 1). The analogous reaction of cis-1a with dimethyl acetylenedicarboxylate (5) gave dimethyl trans-2,5-dihydro-1-methyl-2,5-diphenylpyrrole-3,4-dicarboxylate (trans-6) in accord with orbital-symmetry-controlled reactions (Scheme 2). On the other hand, the reactions of cis-1a and trans-1a with dimethyl dicyanofumarate (7a), as well as that of cis-1a and dimethyl dicyanomaleate (7b), led to mixtures of the same two stereoisomeric dimethyl 3,4-dicyano-1-methyl-2,5-diphenylpyrrolidine-3,4-dicarboxylates 8a and 8b (Scheme 3). This result has to be explained via a stepwise reaction mechanism, in which the intermediate zwitterions 11a and 11b equilibrate (Scheme 6). In contrast, cis-1,2,3-triphenylaziridine (cis-1b) and 7a gave only one stereoisomeric pyrrolidine-3,4-dicarboxylate 10, with the configuration expected on the basis of orbital-symmetry control, i.e., via concerted reaction steps (Scheme 10). The configuration of 8a and 10, as well as that of a derivative of 8b, were established by X-ray crystallography.

The three-component reaction of (R)- or (S)-1-phenylethylamine (6), formaldehyde, and an α-(hydroxyimino) ketone 5, i.e., 3-(hydroxyimino)butan-2-one (5a) or 2-(hydroxyimino)-1,2-diphenylethanone (5b), yields the corresponding enantiomerically pure 1-(1-phenylethyl)-1H-imidazole 3-oxide 7 in high yield (Schemes 2 and 3). The reactions are carried out either in MeOH or in AcOH. Smooth transformations of the N-oxides into optically active 1-(1-phenylethyl)-1H-imidazoles 10 and 2,3-dihydro-1-(1-phenylethyl)-1H-imidazole-2-thiones 11 are achieved by treatment of 7 with Raney-Ni and 2,2,4,4-tetramethyl-3-thioxocyclobutanone (12), respectively (Scheme 4).

Iodide-containing nitro-Grela-type catalysts have been synthesized and applied to ring closing metathesis (RCM) and cross metathesis (CM) reactions. These new catalysts have exhibited improved efficiency in the transformation of sterically, non-demanding alkenes. Additional steric hindrance in the vicinity of ruthenium related to the presence of iodides ensures enhanced catalyst stability. The benefits are most apparent under challenging conditions, such as very low reaction concentrations, protic solvents or with the occurrence of impurities.

A straightforward methodology for the formation of both symmetrical and non-symmetrical hetaryl thioketones is given.

The reaction of the methyl (dialkoxyphosphinyl)-dithioformates (= methyl dialkoxyphosphinecarbodithioate 1-oxides) 10 with CH2N2 at − 65° in THF yielded cycloadducts which eliminated N2 between − 40 and − 35° to give the corresponding phosphonodithioformate S-methanides ( =methylenesulfonium (dialkoxyoxidophosphino)(methylthio)methylides) 11 (Scheme 3). These reactive 1,3-dipoles were intercepted by aromatic thioketones to yield 1,3-dithiolanes. Whereas the reaction with thiobenzophenone (12b) led to the sterically more congested isomers 15 regioselectively, a mixture of both regioisomers was obtained with 9H-fluorene-9-thione (12a). Trapping of 11 with phosphono- and sulfonodithioformates led exclusively to the sterically less hindered 1,3-dithiolanes 16 and 18, respectively (Scheme 4). In addition, reactive CC dipolarophiles such as ethenetetracarbonitrile, maleic anhydride, and N-phenylmaleimide as well as the NN dipolarophile dimethyl diazenedicarboxylate were shown to be efficient interceptors of 11 (Scheme 5).

The thiocarbonyl S-methylides 3a–c, generated in situ by thermal decomposition of the corresponding 2,5-dihydro-1,3,4-thiadiazoles, undergo [3+2] cycloadditions with diphenyl trithiocarbonate (5a) to give 1,3-dithiolanes. The regioselectivity of the reaction of the cycloaliphatic dipoles 3b and 3c is reversed in comparison with that of the aromatic 3a. A mixture of both regioisomeric cycloadducts is formed in the reaction between 3b and methyl dithiobenzoate (6a), whereas only one regioisomer is obtained with thiophthalide (7). Dialkyl phosphonodithioformates 8 are shown to be efficient C=S dipolarophiles in reactions with thiocarbonyl S-methylides 3a–3d, affording 1,3-dithiolane-4-phosphonates. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The crystal structures of dimethyl 2,2,4,4-tetramethyl-3-oxocyclobutane-1-spiro-5′-3′,4′-diphenyl-(1,3)-thiazolidine-2′,2′-dicarboxylate, C26H29NO5S for V, and dimethyl 3,4-diphenyl-5-isopropylidene-(1,3)-thiazolidine-2,2-dicarboxylate, C22H23NO4S for VI, have been solved. The 1,3-thiazolidine ring of compound V has got twisted conformation, while in compound VI this ring adopts envelope. In both structures short inter- and intramolecular contacts were found, which can be recognized as hydrogen bonds.

The crystal and molecular structures of (r-2, c-4)-3-benzyl-2,4,5,5-tetraphenyl-1,3-thiazolidine are investigated showing the existence of C(sp2)–H⋯S and C(sp2)–H⋯N intramolecular contacts. The analysis of geometrical parameters shows that C–H⋯S contacts may be treated as hydrogen bonds but C–H⋯N do not fulfil the geometrical criteria of the existence of H-bonds. The B3LYP/6-311+G* single point calculations were performed to obtain wave functions applied later for ‘atoms in molecules’ (AIM) study. The analysis of bond critical points based on the Bader theory (AIM) supports the existence of intramolecular C–H⋯S H-bonds.

The thermal reaction of 1-substituted 2,3-diphenylaziridines 2 with thiobenzophenone (6a) and 9H-fluorene-9-thione (6b) led to the corresponding 1,3-thiazolidines (Scheme 2). Whereas the cis-disubstituted aziridines and 6a yielded only trans-2,4,5,5-tetraphenyl-1,3-thiazolidines of type 7, the analogous reaction with 6b gave a mixture of trans- and cis-2,4-diphenyl-1,3-thiazolidines 7 and 8. During chromatography on SiO2 , the trans-configured spiro[9H-fluorene-9,5'-[1,3]thiazolidines] 7c and 7d isomerized to the cis-isomers. The substituent at N(1) of the aziridine influences the reaction rate significantly, i.e., the more sterically demanding the substituent the slower the reaction. The reaction of cis-2,3-diphenylaziridines 2 with dimethyl azodicarboxylate (9) and dimethyl acetylenedicarboxylate (11) gave the trans-cycloadducts 10 and 12, respectively (Schemes 3 and 4). In the latter case, a partial dehydrogenation led to the corresponding pyrroles. Two stereoisomeric cycloadducts, 15 and 16, with a trans-relationship of the Ph groups were obtained from the reaction with dimethyl fumarate (14; Scheme 5); with dimethyl maleate (17), the expected cycloadduct 18 together with the 2,3-dihydropyrrole 19 was obtained (Scheme 6). The structures of the cycloadducts 7b, 8a, 15b, and 16b were established by X-ray crystallography.

This work aimed to identify natural dyes in extracts from Coptic fibres. The objects examined originate from fourth- to twelfthcentury AD Egypt. Chromatographic separations of all the samples were carried out using reversed-phase HPLC (high performance liquid chromatography) with UV- Vis detection and fluorescence detection. Fluorescence detection proved to be better than UV- Vis diode array detection for the determination of some compounds. Selected samples were analysed with HPLC-MS (HPLC-mass spectroscopy) which confirmed the LC-UV findings and allowed the detection and identification of additional compounds. Most of the dyes mentioned in the literature as having been used by Copts were detected: Armenian cochineal, flavonoid yellow dyes, indigotin, lac dye, madder and tannins. Some new compositions ofsignificant colours were also discovered, which had not been reported previously in Coptic textiles. Elemental analysis using SEM-EDS (scanning electron microscopy-energy dispersive spectroscopy) was performed to identify mordants.

The crystal and molecular structures of 3-methyl-2,4-diphenyl-(1,3)-thiazolidine-5-spiro-2‘-adamantane and 3-methyl-2,4,5,5-tetraphenyl-(1,3)-thiazolidine are investigated showing the existence of C(sp2)−H···S and C(sp2)−H···N intramolecular contacts. The use of the Bader theory shows that C−H...S interactions existing in crystal structures may be treated as weak H bonds. The C−H...N and C−H...S interactions are also analyzed here for simple modeled complexes of (1,3)-thiazolidine as the proton acceptor and simple proton donators: HF, H2O, C2H4, and C2H2 molecules. The calculations for these complexes were performed within the DFT method, B3LYP/6-311++G** level of theory. The bond critical points (BCPs) were found for these modeled systems and the analysis of the electron densities and their Laplacians at BCPs was performed.

High performance liquid chromatography with UV–Vis detection and post-column derivatization with fluorimetric detection was used for analysis of dyes used in Coptic textiles. To obtain the best separation of analyzed compounds composition of mobile phase was optimized. The best results were obtained for 25 mM phosphoric buffer at pH 2.5 with gradient change of methanol concentration (Table 1). As post-column reagents used to enhance fluorescence signal of analyzed compounds, solutions of Al(III), Ga(III), In(III), and Zn(II) were used. The highest increase of fluorescence signal was observed for Ga(III) and 10 mM solution of this ion was used for investigation of plant extracts and extracts from Coptic textiles.

The reaction of 2,2,4,4-tetramethyl-3-thioxocyclobutanone (1) with cis-1-alkyl-2,3-diphenylaziridines 5 in boiling toluene yielded the expected trans-configured spirocyclic 1,3-thiazolidines 6 (Scheme 1). Analogously, dimethyl trans-1-(4-methoxyphenyl)aziridine-2,3-dicarboxylate (trans-7) reacted with 1 and the corresponding dithione 2, respectively, to give spirocyclic 1,3-thiazolidine-2,4-dicarboxylates 8 (Scheme 2). However, mixtures of cis- and trans-derivatives were obtained in these cases. Unexpectedly, the reaction of 1 with dimethyl 1,3- diphenylaziridine-2,2-dicarboxylate (11) led to a mixture of the cycloadduct 13 and 5-(isopropylidene)-4-phenyl-1,3-thiazolidine-2,2-dicarboxylate (14), a formal cycloadduct of azomethine ylide 12 with dimethylthioketene (Scheme 3). The regioisomeric adduct 16 was obtained from the reaction between 2 and 11. The structures of 6b, cis-8a, cis-8b, 10, and 16 have been established by X-ray crystallography.

The reaction of fluoral hydrate with carbohydrazides in methanol in the presence of molecular sieves (4 A) gave the desired N-acylated fluoral hydrazones (3a–f) in fair yields. Treatment of the latter with mercaptoacetic acid in benzene led to the corresponding 2-trifluoromethyl-1,3-thiazolidinone derivatives (4a–f), whereas the reaction with acetic anhydride gave 3-acetyl-2,3-dihydro-2-trifluoromethyl-1,3,4-oxadiazoles (5a–f). The structures of each type of product have been established by X-ray crystallography.

A convenient synthesis of α-(aziridin-2-yl)-α-(trifluoromethyl) alcohols starting with ethyl aziridine-2-carboxylates is reported. Grignard reaction with the corresponding Weinreb amides led to aziridin-2-yl ketones, and subsequent treatment with Ruppert-Prakash reagent gave the trimethylsilylated target compounds as mixtures of diastereoisomers, which were desilylated with TBAF. In the case of ethyl 1-((S)-1-phenylethyl)aziridine-2-carboxylate, (S,S)- and (S,R)-aziridin-2-yl ketones were obtained, separated chromatographically and transformed into the desired enantiomerically pure α-trifluoromethylated alcohols.

The reaction of 1,2-di(1-adamantyl)-2-thioxoethanone (4c) with diazomethane and 2-diazopropane yielded 2-acylthiiranes 6a and 6b, respectively, and no 1,3-oxathioles of type 7 were formed. The reaction course is explained via [2+3]-cycloaddition, elimination of N2, and 1,3-dipolar electrocyclization of the intermediate acylsubstituted thiocarbonyl ylides of type 1. The failure of the competitive 1,5-dipolar electrocyclization is a result of the sterically unfavorable conformation of 1a.

Enantiomerically pure (R)-1-(1-phenylethyl)imidazoles 4a,b can be prepared conveniently from α-(hydroxyimino)ketones 1, (R)-1-phenylethylamine and formaldehyde, followed by deoxygenation with Raney-Ni. Similarly, the reaction with (R,R)-trans-cyclohexane-1,2-diamine yields enantiomerically pure (R,R)-trans-1,1'-cyclohexane-1,2-diyl)imidazoles 4c,d. Alkylation of these imidazole derivatives with alkylbromides leads to the corresponding 3-alkylimidazolium bromides 6 and 8, respectively, which on treatment with sodium tetrafluoroborate are transformed into the corresponding tetrafluoroborates 7 and 9. Whereas some of the imidazolium salts 7 show properties of chiral ionic liquids, the bis-imidazolium tetrafluoroborates 9 are high-melting crystalline materials.

The reaction of methyl (diethylphosphoryl)dithioformate (6) with diaryldiazomethanes 7a–d in THF at −60 °C to room temperature followed by desulfurization is shown to be a convenient method for the preparation of 2,2-disubstituted 1-(methylsulfanyl)vinyl phosphonates 8a–d. The analogous reactions with 2-diazoacenaphthen-1-one (7f) or 2-diazocamphor (7g) in refluxing THF yield selectively the corresponding (Z)- and (E)-vinyl phosphonates 8f and 8g, respectively. These products can be easily oxidized to the vinylsulfoxides 13 and vinylsulfones 14. On the other hand, methyl (diethylphosphoryl)dithioformate (6) and 2-diazo-1,2-diphenylethanone (7e) in boiling THF react to give the 1,3-oxathiole 12. All these reactions occur via an intermediate thiocarbonyl ylide 11 followed by 1,3-dipolar electrocyclization and sulfur extrusion or 1,5-dipolar electrocyclization.

Polycyclic, nonenolizable cycloaliphatic thioketones 1a and 1b react smoothly with the lithium salt of diethyl methylphosphonate 7 in THF solution at −40°C to afford products of the carbophilic attack exclusively. Quenching of the obtained lithium thiolates with alkyl iodides yields sulfanes of type 9 or 11, respectively, in good yields. 1-Fluoro-2,4-dinitrobenzene was shown to act as an arylating agent. In the case of the “cage” thioketone 1b, the carbanion of salt 7 approaches the CS bond from the exo-side exclusively. In contrast to the parent carbonyl compounds, thioketones 1 show no tendency to undergo the conversion analogous to the Horner–Wadsworth–Emmons reaction, which would result in the formation of an olefinic product. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:182–187, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20390

The reaction of (trimethylsilyl)diazomethane with methyl (diethoxyphosphonyl)dithioformate (2), after elimination of N2 at –35°C, yields the 4,5-bis(trimethylsilyl)-1,3-dithiolane-2-phosphonate (8). This product is the result of the dimerization of the intermediate silylated thiocarbonyl ylide (4b) to give the cyclic sulfonium ylide (7), followed by the elimination of a disubstituted carbene. Trapping of the intermediate (4b) with maleimide (9), maleic anhydride (10), thiobenzophenone (11), and the phosphonylated dithioformate (2) yields the corresponding [2+3] cycloadducts (12), (13), (14b), and (18), respectively. The crystal structures of 13 and 14b have been established by X-Ray crystallography.

The [3+2]-cycloaddition of (trimethylsilyl)diazomethane (7) with 9H-fluorene-9-thione (1) at –60°C yields the spirocyclic 2,5-dihydro-5-trimethylsilyl-1,3,4-thiadiazole 10, which eliminates nitrogen at room temperature to give the 1,4-dithiane derivative 13 by dimerization of the intermediate fluorenethione (trimethylsilyl)methanide (11). This thiocarbonyl ylide can be trapped by 1 to give the 2-trimethylsilyl-1,3-dithiolane 14 via [3+2]-cycloaddition. Furthermore, the 1,3-dipole 11 undergoes successfully [3+2]-cycloadditions with the C=S group of the phosphonyldithioformate 15 as well as with the C=C dipolarophiles maleic anhydride (18a) and N-(cyclohexyl)maleimide (18b). The structures of 13 and 14 have been established by X-ray crystallography.

Polycyclic, nonenolizable cycloaliphatic thioketones 1a and 1b react smoothly with the lithium salt of diethyl methylphosphonate 7 in THF solution at −40°C to afford products of the carbophilic attack exclusively. Quenching of the obtained lithium thiolates with alkyl iodides yields sulfanes of type 9 or 11, respectively, in good yields. 1-Fluoro-2,4-dinitrobenzene was shown to act as an arylating agent. In the case of the “cage” thioketone 1b, the carbanion of salt 7 approaches the CS bond from the exo-side exclusively. In contrast to the parent carbonyl compounds, thioketones 1 show no tendency to undergo the conversion analogous to the Horner–Wadsworth–Emmons reaction, which would result in the formation of an olefinic product. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:182–187, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20390