Photosonosynthesis of 1,2,4-tris(methylthio)-3-H-hexafluoro-n-butane

The preparation of neat 1,2,4-tris(methylthio)-3-H-hexafluoro-n-butane is described. The mechanism, which involves the elimination of hydrogen fluoride with the subsequent isomerization in forming the $\text{cis}$- and $\text{trans-}$ 1,2,4-tris(methylthio)hexafluoro-l-butene, is discussed. This study also supports the presence of methanethiol as an intermediate during the photosonoreaction of bis(methylthio)hexafluoro-2-butene with an excess of methyl disulfide.     

Synthesis and reactions of 3-acetyl-6-methyl-2-(methylthio)pyridine

A reaction of methyllithium with 3-cyano-6-methylpyridine-2(1 H)-thione followed by alkylation of the resulting 3-acetylpyridinethione, or a direct reaction of methyllithium with 3-cyano-6-methyl-2-(methylthio)pyridine, afforded 3-acetyl-6-methyl-2-(methylthio)pyridine. The ketone obtained was examined in bromination reactions under various conditions. Bromi-nation in methanol or chloroform, proceeding through the formation of sulfonium bromides, gave substituted 3-(bromoacetyl)pyridine. A reaction of 3-acetyl-6-methyl-2-(methyl-thio)pyridine with N-bromosuccinimide in CCl4 afforded N-(pyridinesulfenyl)succinimide. The bromo ketone was used for the synthesis of various heterocyclic compounds.     

On the syntheses and some reactions of bis- and tris(methylthio)thiophenes

Reaction between various thienyllithium derivatives and dimethyl disulfide has been used for the preparation of 2,5-, 2,3-, and 3,4-bis(methylthio)thiophenes, as well as 2,3,4- and 2,3,5-tris(methylthio)thiophenes. Bromination of (methylthio)thiophenes with N-bromosuccinimide was found to be most convenient for the preparation of brominated (methylthio)thiophenes such as 3-bromo-2,5-bis(methylthio)- and 5-bromo-2,3-bis(methylthio)thiophene, 3,4-dibromo-2,5-bis(methylthio)-, 2,5-dibromo-3,4-bis(methylthio)- and 2,3-dibromo-4,5-bis(methylthio)thiophene as well as 3-bromo-2,4,5-tris(methylthio)thiophene. The reaction of methylthio substituted thienyllithium derivatives with methyl chloroformate was used for the syntheses of methyl methylthio substituted thiophenecarboxylates and using 1/3 of an equivalent for the direct preparation of methylthio substituted 3-thienylcarbinols as tris[2,4,5-tris(methylthio)-3-thienyl]carbinol.     

Synthesis of 3-hydroxy-1-methyl-2-(methylthio) pyrrole from methyl isothiocyanate and prop-2-yn-1-ol

A methylated adduct of lithiated 1-(1-ethoxyethoxy)allene and methyl isothiocyanate undergoes intramolecular cyclization in the presence of CuBr to give 3-(1-ethoxyethoxy)-1-methyl-2-(methylthio)pyrrole. The methanolysis of the latter affords 3-hydroxy-1-methyl-2-(methylthio)pyrrole. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1645–1647, September, 2000.     

Reactions of 3-cyano-2-(methylthio)pyridines with butyllithium

Reactions of substituted 3-cyano-2-(methylthio)pyridines with butyllithium were studied. The reactions afforded 3-pentanoylpyridines, 2,3-dihydrothieno[2,3-b]pyridine, or 1-amino-2,7-naphthyridine, depending on the starting substrate and the reaction conditions.     

Bis(methylthio)tetracenes: synthesis, crystal-packing structures, and OFET properties

5,12-Bis(methylthio)tetracene (2) and 5,11-bis(methylthio)tetracene (3) were synthesized. DFT calculations indicate that the HOMO and LUMO energy levels of 2 and 3 are lowered by 0.13-0.24 eV and their HOMO-LUMO energy gaps are reduced by 0.1 eV relative to those of tetracene. X-ray crystallographic data revealed that 2 is arranged as a result of a 1-D slipped-cofacial π-stacking with S-S and S-π interactions, similar to the packing arrangement of 6,13-bis(methylthio)pentacene (1), whereas 3 exhibits a herringbone packing arrangement without S-S interactions. The OFET devices fabricated using spin-coated films of soluble 1 and 2, with a bottom-contact device configuration, exhibited hole mobilities as high as 1.3 × 10(-2) and 4.0 × 10(-2) cm(2) V(-1) s(-1) with current on/off ratios of over 10(5) and 10(4), respectively.     

Regioselective synthesis of 1-aryl-3,4-substituted/annulated-5-(methylthio)pyrazoles and 1-aryl-3-(methylthio)-4,5-substituted/annulated pyrazoles

[reaction: see text] Highly efficient and regioselective synthesis of 1-aryl-3,4-substituted/annulated-5-(methylthio)pyrazoles and 1-aryl-3-(methylthio)-4,5-substituted/annulated pyrazoles has been reported via cyclocondensation of arylhydrazines with either alpha-oxoketene dithioacetals or beta-oxodithioesters.     

Studies on topical antiinflammatory agents. IV. 21-(Alkylthio)acetates and (methylthio)methoxides of corticosteroids

A series of 21-(alkylthio)acetates and 21-(methylthio)methoxides of corticosteroids were synthesized and examined for vasoconstrictive activities. The activities of seven compounds were equal to or greater than that of 9 alpha-fluoro-11 beta,21-dihydroxy-16 beta-methyl-17 alpha-valeryloxy-1,4-pregnadiene-3,20-dione (betamethasone 17-valerate, BV). Among them, betamethasone 21-(methylthio)acetate 17-propanoate (2Ca) was found to have the most potent activity, which is superior to that of BV. A structure-activity relationship study revealed that substitution of the 21-hydroxy group of corticosteroids with the (methylthio)acetate function is a useful approach for obtaining potent activity.     

3-Cyanopyridine-2(1H)-thiones and 3-cyano-2-(methylthio)pyridines in the synthesis of substituted 3-(aminomethyl)pyridines

The reactions of substituted 3-cyanopyridine-2(1H)-thiones and 3-cyano-2-(methylthio)pyridines with lithium aluminum hydride in anhydrous diethyl ether afforded the corresponding 3-aminomethyl derivatives, which were used in the synthesis of the corresponding amides.     

Unusual Thermal Rearrangements of N-Cyclohexylidene-4-methyl-1-(methylthio)penta-1,3-dien-1-amine

We have observed unusual thermal rearrangements of N-cyclohexylidene-4-methyl-1-(methylthio)penta-1,3-dien-1-amine to 4,4-dimethyl-2-(methylthio)-3,3a,4,4a,5,6,7,8-octahydrobenzo[4,1]cyclobuta-[1,2-b]pyrrole and 1-cyclohexyl-5-methylpyridine-2(1H)-thione.     

The kinetics and mechanisms of the gas phase elimination of 4-(methylthio)-1-butyl acetate and 1-chloro-4-(methylthio)-butane

The gas phase elimination of 4-(methylthio)-1-butyl acetate and 1-chloro-4-(methylthio)-butane has been investigated in a seasoned, static reaction vessel over the temperature range of 310–410°C and the pressure range of 46–193 Torr. The presence of the inhibitors propene, cyclohexene, and/or toluene had no effect on the rates. The reactions are homogeneous, unimolecular, and obey a first-order rate law. The rate coefficients are given by the following Arrhenius equations: for 4-(methylthio)-1-butyl acetate, log k₁(s^?1) = (12.32 ± 0.29) ? (192.1 ± 3.6) kJ/mol/2.303RT; for 1-chloro-4-(methylthio)-butane, log k₁(s^?1) = (12.23 ± 0.59) ? (175.7 ± 6.8) kJ/mol/2.303RT. The CH₃S substituent in 1-chloro-4-(methylthio)-butane has been found to participate in the elimination reaction, where tetrahydrothiophene and methyl chloride formation may result from an intimate ion-pair type of mechanism. The yield of a cyclic product in gas phase reactions provides additional evidence of an intimate ion pair mechanism through neighboring group participation in gas phase elimination of special types of organic halides.     

Domino carbocationic rearrangement of alpha-[bis(methylthio)methylene]alkyl-2-(3/2-indolyl) cyclopropyl ketones

Domino carbocationic rearrangement of a number of substituted 3- and 2-indolylcyclopropyl ketones with an alpha-bis(methylthio)methylene group in the presence of various protic/Lewis acids yields a variety of products, mainly the pentaleno fused indoles and the carbazole derivatives.     

Formation of furo[3,2- c ]quinolone-2-carbonitriles and 4-oxo-4,5-dihydrofuro[3,2- c ]quinolone-2-carboxamides from reaction of quinoline-2,4-diones with 2-[bis(methylthio)methylene]malononitrile

Quinoline-2,4-diones reacted with 2-[bis(methylthio)methylene]malononitrile in DMF/Et3N to produce 3-(methylthio)-4-oxo-4,5-dihydrofuro[3,2-c]quinolone-2-carbonitriles and 3-(methylthio)-4-oxo-4,5-dihydrofuro[3,2-c]quinolone-2-carboxamides in state of 2-imino-substituted 4-(methylthio)-5,6-dihydro-2H-pyrano[3,2-c]quinolone-3-carbonitriles. The structures of all new products were proved using NMR, IR, and mass spectral data. The possible mechanism for the reaction is also discussed.     

A novel reaction of 2-(arylamino)-1-(methylthio)-1-tosylethenes with hydrogen iodide leading to quinoline derivatives

The reaction of 2-(arylamino)-1-(methylthio)-1-tosylethenes (4) with hydrogen iodide in refluxing toluene gave 3-tosyl-2-(tosylmethyl)quinoline derivatives (6) in good yields. In this reaction, hydrogen iodide dose not only reductively removes the methylthio group of 4 to form an intermediary 1-(arylamino)-2-tosylethene (5), but also serves as a protic catalyst for the subsequent dimeric cyclization of 5 to lead to the quinoline derivatives (6).     

Synthese von (Methylthio)penam-Derivaten durch Keten-Addition an 4,5-Dihydro-5-(methylthio)-1,3-thiazole

Synthesis of (Methylthio)penam Derivatives via Keten Addition onto 4,5-Dihydro-5-(methylthio)-1,3-thiazoles The 4,5-dihydro-5-(methylthio)-2-phenyl-1,3-thiazoles 3a and 3b , easily prepared from the corresponding 1,3-thiazol-5(4H)-thiones and MeLi, react with dichloroacetyl chloride ( 5a ) and acidoacetyl chloride ( 5b ) in the presence of Et₃N to give (methylthio)penam derivatives 6 (Table 1). The reaction mechanism is either a [2 + 2] cycloaddition of in situ generated ketene or a two-step reaction (Scheme 2). The structure of 6f has been confirmed by X-ray crystallography (Fig. 2). The relative configuration of 6a-e follow from comparison of their ¹H-NMR spectra with those of 6f (Fig. 1). The 6-azidopenams 6d and 6f have been reduced to aminopenams 8a and 8b , respectively. Acylation of 8a with phenacetyl chloride yields 9 (Scheme 4).     

Simple one-pot multicomponent approach to polyfunctionalized 2-amino-1-methyl-6-(methylthio)-5-nitro-4-aryl-1,4-dihydropyridine-3-carbonitriles

A series of polyfunctionalized 2-amino-1-methyl-6-(methylthio)-5-nitro-4-aryl-1,4-dihydropyridine-3-carbonitriles have been prepared using a multicomponent condensation reaction between aromatic aldehydes, malononitrile, and (Z) N-methyl-1-(methylthio)-2-nitroethenamine in the presence of Et₃N in acetonitrile.     

有机锡2-[(1,2,4-三唑-1-基)甲基硫代]苯甲酸酯的合成与生物活性

通过硫代水杨酸与(1-氯甲基)-1,2,4-三唑盐酸盐在碱性条件下的反应, 合成了2-[(1,2,4-三唑-1-基)甲基硫代]苯甲酸. 利用该酸与(R₃Sn)₂O(R=Et, n-Bu, Ph), Cy₃SnOH(Cy为环己基)或Et₂SnO反应, 得到了5个有机锡羧酸酯. 用X射线单晶衍射测定了三正丁基锡2-[(1,2,4-三唑-1-基)甲基硫代]苯甲酸酯的晶体结构. 在该化合物中, 锡为五配位的三角双锥结构. 该化合物通过三唑四位氮原子与锡配位, 形成一维链状配位高分子. 初步的生物活性测试结果表明, 所有的有机锡化合物都表现出了明显的抗真菌活性.     

2-phenyl-4-bis(methylthio)methyleneoxazol-5-one: versatile template for diversity oriented synthesis of heterocycles

4-Bis(methylthio)methylene-2-phenyloxazol-5-one (1) has been shown to be a versatile template for the synthesis of novel heterocyclic scaffolds. The key protocol involves nucleophilic ring opening of 1 with various primary aliphatic, aromatic amines and diamines to give open-chain amide adducts which are transformed into 4-bis(methylthio)methylene-2-phenyl-1-alkyl/arylimidazol-5-(4H)-ones (5) in good yields in the presence of anhydrous NaOAc/AcOH. Similarly, the amide adducts 4h-i from 3,4-dimethoxyphenylethylamine and tryptamine undergo interesting rearrangement in the presence of POCl(3) to furnish 1-(2-phenyl-5-methylthio-4-thiazolyl)dihydroisoquinoline and β-carboline derivatives 8-9 in good yields. The amide adduct 14 from o-phenylenediamine on exposure to refluxing acetic acid or in the presence of Ag(2)CO(3) affords substituted 3H-1,5-benzodiazepinone, 2-(5-methylthio-2-phenyl-4-oxazolyl)-1H-benzimidazole and trisubstituted oxazole (15-17), whereas the bis-adduct from ethylenediamine yields ethylene bridge tethered bis-imidazole 23 and bis-oxazole 24 under similar reaction conditions. Probable mechanisms for the formation of various products have been suggested.     

Synthesis and thermal decomposition of haloalkoxy-sym-triazines 5. Thermal decomposition of 2-methoxy(methylthio)-4-[1,3-dichloropropoxy(3-chloro-1-propoxy)]-6-dimethylamino-sym-triazines

2-Methoxy (methylthio)-4-(1, 3-dichloropropoxy)-and 2-methoxy (methylthio)-4-(3-chloro-1-propoxy)-6-dimethylamino-sym-triazines were synthesized and subjected to thermolysis, as a result of which chloromethyltetrahydrooxazolo-, N-2, 3-di-chloropropyl-sym-triazines and tetrahydrooxazino-and tetrahydrothiazino-sym-triazines, respectively, were obtained. The thermolysis of haloalkoxy-sym-triazines proceeds via a concerted mechanism. See [4] for communication 4. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 411–415, March, 1980.     

A concise synthesis of turneforcidine via a metalloiminium ion cyclization terminated by the 2-(methylthio)-3-(trimethylsilyl)-1-propenyl moiety

A concise synthetic route to racemic turneforcidine (1) is described that relies on the stereocontrolled cyclization of the 2-(methylthio)-3-(trimethylsilyl)-1-propenyl bearing imine 5 in the presence of TiCl(4). Reaction: see text.