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1.
Alain Turck Nelly Pl Pamla Pollet Guy Quguiner 《Journal of heterocyclic chemistry》1998,35(2):429-436
In the pyridazine series, the use of tert-butylsulfinyl and tert-butylsulfonyl as ortho directing groups for metalation has been tested. Various functionalized products were obtained in good yields. In the case of 3-tert-butylsulfinyl-6-methoxypyridazine, the metalation was regioselective in ortho to the sulfinyl group. The metalation of 2-tert-butylsulfinyl and 2-tert-butylsulfonylpyrazine gave low to moderate yields. Synthesis of diazinesulfonamides were improved and the metalation of N-tert-butylsulfonamidopyrazine was achieved. 相似文献
2.
A variety of rearrangement reactions have been documented in the gas phase ion chemistry of styryl sulfoxides and sulfones. The styryl group rearranges from sulfur to oxygen as evidenced by loss of SCH3 from methyl styryl sulfoxide and loss of SOCH3 from the corresponding sulfone. The resulting m/e 119 ion loses carbon monoxide in one fragmentation route and alternatively loses a hydrogen atom from the aromatic nucleus to produce the benzofuran molecule ion via an electrophilic aromatic ring closure reaction. Styryl sulfoxides lose both carbon monoxide and formyl radicals directly from their molecule ions, but the corresponding sulfones do not fragment in this manner. The mechanisms of the above reactions, as well as others, were investigated using substituent and deuterium labeling. The styryl group has been shown to migrate in preference to a phenyl or substituted phenyl group by investigation of the mass spectra of appropriate aryl styryl sulfoxides and sulfones. 相似文献
3.
The reactions of 2,4,6-trinitrotoluene with alkanethiols in the presence of K2CO3 (the molar ratio of the reactants is 1 : 1 : 1) in dipolar aprotic solvents result in selective replacement of the ortho-nitro group to form 2-alkylthio-4,6-dinitrotoluenes, which can be oxidized to the corresponding sulfoxides or sulfones. The second ortho-nitro group can be replaced under the action of one more equivalent of alkanethiol on sulfides as exemplified in PhCH2SH. 相似文献
4.
Melzig L Rauhut CB Naredi-Rainer N Knochel P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(19):5362-5372
The aryl sulfoxide moiety allows an expedient two‐step difunctionalisation of readily available diaryl sulfoxides. Highly functionalised 1,2,4‐trisubstituted arenes and difunctionalised heteroarenes (furans, thiophenes, benzofurans and pyridines) were prepared in a two‐step sequence, triggered by an aryl sulfoxide group. In the first step, the sulfoxide moiety acts as a metallation‐directing group, allowing smooth ortho‐magnesiation with TMPMgCl ? LiCl (TMP=tetramethylpiperidine). After a quenching reaction with an electrophile, the resulting sulfoxide is converted into a second magnesium reagent with iPrMgCl ? LiCl (sulfoxide–magnesium exchange), which can be trapped with various electrophiles. Highly chemoselective TMPMgCl ? LiCl and iPrMgCl ? LiCl are compatible with a broad range of functional groups (e.g., F, Cl, CF3, CN, CO2tBu, alkynyl, ethers, thioethers). Large‐scale reactions (25–40 mmol) and the preparation of fully functionalised furans and thiophenes are also reported. 相似文献
5.
Hayate Saito Keita Yamamoto Yosuke Sumiya Ling‐Jun Liu Keisuke Nogi Satoshi Maeda Hideki Yorimitsu 《化学:亚洲杂志》2020,15(16):2442-2446
C?H iodination of aromatic compounds has been accomplished with the aid of sulfinyl directing groups under palladium catalysis. The reaction proceeds selectively at the peri‐position of polycyclic aryl sulfoxides or at the ortho‐position of phenyl sulfoxides. The iodination products can be further converted via iterative catalytic cross‐coupling at the expense of the C?I and C?S bonds. Computational studies suggest that peri‐C?H palladation would proceed via a non‐directed pathway, wherein neither of the sulfur nor oxygen atom of the sulfinyl group coordinates to the palladium before and at the transition state. 相似文献
6.
Robert Franzén 《高等学校化学研究》2006,22(5):602-605
IntroductionAqueous hydrogen peroxide is considered to be a“green”oxidant with a high oxidation efficiency due toits low molecular weight,cleanness in the oxidationprocess in which only harmless water is produced,lowcost of production and safe transport… 相似文献
7.
Aryl thiolates have unique reactive, redox, electronic, and spectroscopic properties. A practical approach to synthesize peptides containing thiophenylalanine has been developed via a novel Cu(I)-mediated cross-coupling reaction between thiolacetic acid and iodophenylalanine-containing peptides in the solid phase. This approach is compatible with all canonical proteinogenic functional groups, providing general access to aryl thiolates in peptides. Peptides containing thiophenylalanine (pK(a) 6.4) were readily elaborated to contain methyl, allyl, and nitrobenzyl thioethers, disulfides, sulfoxides, sulfones, or sulfonates. 相似文献
8.
Lun Wang Prof. Li Liu Prof. Hanying Zhao 《Angewandte Chemie (International ed. in English)》2023,62(24):e202304073
In the past decades click chemistries including thiol chemistries have found wide applications in the synthesis of well-defined polymers. In this research, a click-declick strategy based on the oxidation of heteroaromatic thioethers and the substitution reactions between the oxidized groups and thiols, is proposed for the synthesis of the cleavable polymers. In proof-of-concept experiments, block copolymers (BCPs) and star-like polymers are synthesized by thiol-phenylsulfone substitution reactions, and heteroaromatic thioethers are produced at the junction points of the BCP chains or on the crosslinking sites of the star-like polymer. The thioethers can be oxidized to heteroaromatic sulfoxides or sulfones, depending on the oxidization condition. It is demonstrated that both sulfoxides or sulfones can have base catalyzed nucleophilic substitution reactions with thiols, leading to the cleavage of the polymers. 相似文献
9.
Dirk Otzen Jürgen Voss Gunadi Adiwidjaja 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1249-1270
2,5-anhydro-3-azido-2-thio-D-lyxofuranosides and 3,5-anhydro-2-azido-3-thio-D-lyxofuranosides were prepared from methyl D-xylofuranoside or methyl D-ribofuranoside via corresponding 2,3-epoxysugars or the 5-O-trityl derivative. The sulfur was introduced into molecules by use of the thio-Mitsunobu reaction. Bicyclic azido-thiosugars were transformed into nucleoside analogues, oxidized to sulfoxides and sulfones, and reduced to bicyclic amino-thiosugars. Structures and configurations of products were determined by NMR spectroscopy or X-ray structure analyses. 相似文献
10.
《Tetrahedron: Asymmetry》2000,11(21):4385-4395
We describe the addition reactions of α-thiocarbanions derived from sulfoxides, thioethers, and sulfones to 2-(p-tolylsulfinyl)cyclohexanones. The high stereoselectivity observed in the formation of the chiral hydroxylic carbon is controlled by the configuration of the sulfinyl group at the substrate, but it is modulated by the nature of the sulfur function at the reagent (SOTol>SO2Ph>SPh). The highly stereoselective formation of the second stereogenic center generated in these reactions from prochiral anions is only achieved with sulfinylcarbanions, the configuration of which controls that of such a center. 相似文献
11.
An unambiguous synthesis of a number of 3-coumaryl phenyl sulfones or sulfoxides have been described which were obtained by the oxidation of the corresponding sulfides with hydrogen peroxide. The sulfides were prepared by the Perkin-Oglialore reaction of o-hydroxyaldehyde with the sodium salt of different S-phenyl thioacetic acids. The sulfones did not exhibit any appreciable antitubercuious activity in the preliminary screening tests. 相似文献
12.
Manijeh Mohraz Wang Jian-qi Edgar Heilbronner Arlette Solladia-Cavallo Firouz Matloubi-Moghadam 《Helvetica chimica acta》1981,64(1):97-112
13C-NMR. and He (Iα) photoelectron spectra of alkyl phenyl sulfides, sulfoxides and sulfones have been used to probe how their conformations depend on the size of the alkyl groups R. The results are interpreted to indicate that in the sulfides the S, R-bond is twisted out of the planar conformation with increasing size of the alkyl group, whereas in the sulfoxides and sulfones the preferred conformation with the S, R-bond perpendicular to the phenyl group plane seems to be independent of the size of R. These conclusions are in agreement with previous work on the alkyl phenyl sulfides and provide strong support for previous conjectures concerning the preferred conformations of alkyl phenyl sulfoxides and sulfones. 相似文献
13.
Vasin V. A. Kostryukov S. G. Razin V. V. 《Russian Journal of Organic Chemistry》2002,38(11):1582-1587
By reactions of 1-R-tricyclo[4.1.0.02,7]heptanes (R = H, Br) with hydrogen sulfide initiated by UV irradiation endo-6-bicyclo[3.1.1]heptanethiols and bis(endo-6-bicyclo[3.1.1]heptyl) sulfides were synthesized. The sulfides were oxidized to the corresponding sulfoxides and sulfones. The results of HBr elimination from the bromine-substituted sulfoxides and sulfones effected by potassium tert-butylate are discussed. The latter reaction results in the recovery of the system of 1-substituted tricyclo[4.1.0.02,7]heptane. 相似文献
14.
Although there have been a relatively large number of publications recently dealing with the reduction of sulfoxides fo sulfides1,2 there are still very few general procedures for the reduction of sulfones to sulfides and none at all, as far as we are aware, for the reduction of sulfones to sulfoxides. In his paper dealing with the use of diisobutylaluminum hydride (DIBAL-H) for the reduction of sulfones to sulfides, for example, Gardner3 points out the inadequacies of the more readily available lithium aluminum hydride for this reduction. We have developed a two part procedure for reducing sulfones 1 to sulfoxides 2 which fills an important gap in the functional group interconversion of organosulfur compounds, the results of which we now describe. 相似文献
15.
A series of 1,3-thiasilacycloalkanes and their S-oxides, S,S-dioxides, and sulfonium salts were studied by the DFT (B3LYP/6-31G*) method. In six-membered sulfoxides, the oxygen atom preferentially occupies the axial position, whereas in the corresponding sulfonium salts the S-alkyl group occupies the equatorial position. The calculation results explain the lower hydrolytic stability of the five-membered rings compared to the six-membered analogs and the lower stability of sulfoxides compared to sulfones. 相似文献
16.
Dieter Scholz 《Monatshefte für Chemie / Chemical Monthly》1981,112(2):241-243
The mild oxidation of sulfides and sulfoxides to sulfones with benzyltriethylammoniumpermanganate in organic solvents is described.
1Scholz, D., in Vorbereitung. 相似文献
17.
Maria Celia Flores Nicholas R. Beller JosÉ Castrillón 《Journal of heterocyclic chemistry》1984,21(6):1737-1739
The preparations of benzo[f]naphtho[1,8-bc]thiepin-12-one, its 6-methyl and 6-methoxy derivatives and their corresponding sulfoxides and sulfones are described. They involve the coupling of suitable halogen naphthyl derivatives with thiophenoxides with the help of copper and the cyclization of the resulting acids with phosphorus pentoxide in benzene. The oxidations to sulfoxides and sulfones were performed with iodo-benzene diacetate and hydrogen peroxide, respectively. The ir and pmr spectra are reported. 相似文献
18.
Paul C. Unangst David T. Connor S. Russell Stabler 《Journal of heterocyclic chemistry》1987,24(3):817-820
The synthesis of novel indole-2-carboxylic acids with amino- and sulfur-containing substituents in the indole 3-position is described. An Ullmann reaction with bromobenzene converted 1H-indoles with 3-(acetylamino)- and 3-(diethylamino)-substituents into 1-phenyl-1H-indoles. Reaction of 3-unsubstituted indoles with thionyl chloride provided indole 3-sulfinyl chlorides, which reacted with alkyl and aryl Grignard reagents to form the corresponding sulfoxides. The indole sulfoxides thus obtained were reduced to sulfides or oxidized to sulfones. 相似文献
19.
Dr. Nurbey Gulia Jarosław Fornalski Adrianna Gumienna Małgorzata Ambroziak Prof. Dr. Sławomir Szafert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(66):e202202449
A method of palladium-catalyzed C−H arylation assisted with a 3,4,4-trimethylpyrazol-5-on directing group, selectively providing mono- and di-ortho-arylated products is reported. Steric hindrance appearing between the directing group and the already introduced aryl substituent enables control of mono- vs. diarylation selectivity by the temperature of the reaction. Taking advantage of this, a series of monosubstituted and disubstituted derivatives were obtained in good yields. Moreover, unsymmetrical double-arylation in a one-pot procedure was developed to give corresponding products in reasonable yields. Additionally, synthesis and X-ray study of intermediate palladium metallacycles of both, the first and second arylation reactions, were conducted. X-ray structure comparison emphasizes the geometrical differences that were consistent with the observed reactivity. Finally, decarboxylative cleavage of the pyrazolone directing group under mild conditions gave synthetically useful hydrazones. The presented solution opens the alternative synthetic way to such ortho arylated derivatives of arylhydrazines. 相似文献
20.
Ahmed I. Khodair Ahmed A. Swelim A. A. Abdel-wahab 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):173-175
Abstract Mass spectra of three sulfones selected to reveal certain structural features were obtained and interpreted. The mass spectra of the two isomeric sulfones, benzyl methyl sulfone and methyl p-tolyl sulfone, were quite different. The spectra showed that rearrangement of sulfones to the isomeric sulfinates occurs under the influence of the electron impact and that the migration of the aryl group is preferred over migration of the alkyl group. 相似文献