Thiophenol nitro

Dilute sodium hydroxide solution. Carboxylic acids (RCOOH), sulphonic acids (RSO3H), phenols (ArOH), thiophenols (ArSH), mer-captans (RSH), imides (RCONHCOR), aryl sulphonamides (AxSOjNHj), arylsulphonyl derivatives of primary amines (AxSOjNHR), oximes (RCH=NOH), primary and secondary nitro compounds (RCH=NOOH and RjC=NOOH-oci forms), and some enols (e.g., of 1 3-diketones... 

However, heterocycles containing thiophenols have not been reported. It has been observed that the thiophe-nolate ion undergoes nucleophilic attack by the halo/ nitro compounds more easily than the phenolate ion in displacement reactions [37-39]. The experimental result shows that the reactivity of 3-nitro-N-phenyl-phthali-mide with 4-methyl-thiophenolate (reaction 1) is 100 times faster than that of 4-methyl phenolate [40] (reaction 2) ... 

Phenyl-thiocyanat kann in alkoholischcr 2 n Schwefelsaure in Thiophenol iiberfiihrt werden (Blei-Kathode). (Nitro-phenyl)-cyan-sulfide ergeben neben etwas Amino-thio-phenol iiberwiegend dimere und heterocyclische Verbindungen (s. S. 687) ... 

The base-catalyzed joint reaction of nitroalkenes with thiophenol in the presence of aldehydes gives y-phenylthio-P-nitro alcohols in one pot (Eq. 4.5).8 The joint reaction of nitroalkenes with thiols and a,p-unsaturated nitriles (or esters) has also been achieved. (Eq. 4.6).9 P-Nitro sulfides thus prepared show unique reactivity toward nucleophiles or tin radicals. The nitro... 

Combining, in tandem, the nitro-aldol reaction with the Michael addition using thiophenol is a good method for the preparation of P-nitro sulfides as shown in Eqs. 4.2 and 4.3. This reaction is applied to a total synthesis of tuberine. Tuberine is a simple enamide isolated from Streptomyces amakusaensis and has some structural resemblance to erbastatin, an enamide which has received much attention in recent years as an inhibitor of tyrosine-specific kinases. The reaction of p-anisaldehyde and nitromethane in the presence of thiophenol yields the requisite P-nitro sulfide, which is converted into tuberine via reduction, formylation, oxidation, and thermal elimination of... 

It is assumed that an excited state charge transfer complex is formed between the nitroaromatic in its first triplet state and the respective substrate. Internal proton transfer is immediately followed by hberation of carbon dioxide. Finally hydrolysis of the hemiacetal Ar —X—CH2OH (X = NH or S) leads to 2-chloro-aniline or thiophenol, respectively. In the decarboxylation of a-phenylthio-acetic acid, some methyl-phenylsulfide is also formed. (7t,7r )-nitroaromatics are more reactive than nitro compounds with lowest (n,7t )-triplets iso). 

Irradiation accelerates the reactions of Scheme 4.1, and the substitution products are formed in 70-80% yields. Acceptors of radicals (e.g., di-tert-butylnitroxyl) or electrons (e.g., m-dinitro-benzene [DNB]) completely inhibit the snbstitution even if the acceptors are added to the reaction mixture in small amonnts. The mentioned snbstitution reactions do not take place when no cyano groups are present in the initial a-phenylsnlphonyl cumene. Hence, the cyano groups send the reaction via the ion-radical pathway. Like the nitro gronp, the cyano group promotes the formation of anion-radical, which originates on one-electron transfer from the thiophenolate or malonate ions to the substrate. 

The chemical entrainment method was used by Ono et al. (1979) to eliminate the nitro group in nitroalkene derivatives. On simple mixing with thiophenol and sodium sulfide in DMF, nitro aryl olefins substitute hydrogen for the nitro group (Scheme 5.9). 

Scheme 6.2 represents Sj j l substitution that takes place when sodium thiophenolate attacks e,4-tert-butyl-c,2-methyl-fl,4-nitro-e,4-(4-nitrophenyl) cyclohexane. Light irradiation stimulates the reaction. It is carried out under nitrogen in HMPA. The ion-radical type of the process has been established by means of inhibitors. It was found that the stereochemical outcome of the reaction depends on the concentration of the PhSNa nucleophile. At a low concentration of PhSNa, the reaction leads to a mixture of phenylthiyl derivatives the content of a,SPh-substituted product is higher than that of c,SPh product by 20%. At a high concentration of PhSNa, the reaction produces practically a single stereoisomer bearing the a-PhS group. 

The chemistry of nitro compounds forms the basis of a number of well-known processes, such as the Henry or the Nef reactions . Transformations such as the latter permit the interconversion between nitro and other functional groups and are therefore of prime importance. The most commonly employed methods for the reduction of primary nitroalkanes to oximes involve the use of BusSnH, Se/NaBH4, CS2 or SnCla (often in combination with thiophenol) . 

The lower members of the homologous series of 1. Alcohols 2. Aldehydes 3. Ketones 4. Acids 5. Esters 6. Phenols 7. Anhydrides 8. Amines 9. Nitriles 10. Polyhydroxy phenols 1. Polybasic acids and hydro-oxy acids. 2. Glycols, poly-hydric alcohols, polyhydroxy aldehydes and ketones (sugars) 3. Some amides, ammo acids, di-and polyamino compounds, amino alcohols 4. Sulphonic acids 5. Sulphinic acids 6. Salts 1. Acids 2. Phenols 3. Imides 4. Some primary and secondary nitro compounds oximes 5. Mercaptans and thiophenols 6. Sulphonic acids, sulphinic acids, sulphuric acids, and sul-phonamides 7. Some diketones and (3-keto esters 1. Primary amines 2. Secondary aliphatic and aryl-alkyl amines 3. Aliphatic and some aryl-alkyl tertiary amines 4. Hydrazines 1. Unsaturated hydrocarbons 2. Some poly-alkylated aromatic hydrocarbons 3. Alcohols 4. Aldehydes 5. Ketones 6. Esters 7. Anhydrides 8. Ethers and acetals 9. Lactones 10. Acyl halides 1. Saturated aliphatic hydrocarbons Cyclic paraffin hydrocarbons 3. Aromatic hydrocarbons 4. Halogen derivatives of 1, 2 and 3 5. Diaryl ethers 1. Nitro compounds (tertiary) 2. Amides and derivatives of aldehydes and ketones 3. Nitriles 4. Negatively substituted amines 5. Nitroso, azo, hy-drazo, and other intermediate reduction products of nitro com-pounds 6. Sulphones, sul-phonamides of secondary amines, sulphides, sulphates and other Sulphur compounds... 

T etra (2 nitrophenylmercapto) l,4 benzo quinone, (02N.C6H4.S)4C602 mw 720.74, Ni 7.78% bm-yel prisms(from nitroben2), mp-e tpl violently when heated diffc sol in common org solvs was prepd by treating tetrachloro-l,4-ben-2oquinone(chloranil) with an excess of 2-nitro-thiophenol in ale... 

Halide displacement by thioanions such as thioalkoxides, thiocyanate and sulfite, can be readily carried out under PTC conditions in activated arenes. The reaction of nitro- and dinitro-aryl halides with thiophenol and NaOH in the presence of an ammonium or phosphonium salt catalyst proceeds readily in toluene at room temperature to give the phenyl aryl sulfides in nearly quantitative yield.189 Excellent yields of thiocyanoarenes were obtained from the reaction of the 2,4-dinitrohalobenzenes with KSCN in toluene at 90 C with a tetraalkyl onium salt PTC catalyst.190... 

Formation of a symmetrical sulphide (a) (e.g. dipropyl sulphide, Expt 5.204), is conveniently effected by boiling an alkyl halide (the source of carbocations) with sodium sulphide in ethanolic solution. Mixed sulphides (b) are prepared by alkylation of a thiolate salt (a mercaptide) with an alkyl halide (cf. Williamson s ether synthesis, Section 5.6.2, p. 583). In the case of an alkyl aryl sulphide (R-S Ar) where the aromatic ring contains activating nitro groups (see Section 6.5.3, p. 900), the aryl halide is used with the alkyl thiolate salt. The alternative alkylation of a substituted thiophenol is described in Section 8.3.4, p. 1160. The former procedure is illustrated by the preparation of isobutyl 2,4-dinitrophenyl sulphide (Expt 5.205) from l-chloro-2,4-dinitrobenzene and 2-methylpropane-1-thiol. 

There have been several reports of the use of intramolecular displacements of nitro groups in the synthesis of heterocyclic compounds. Thus, reaction16 of the intermediate (2) with a strong base in DMF results in the substitution of a nitro group by the amide function to yield a dibenzothiazepinone derivative (3). Nucleophilic addition across the double bond of 2,4,6-trinitrostyrene may occur with thiophenol, aniline, and aliphatic amines. The adducts so formed with primary amines may undergo intramolecular substitution of an o-nitro group to give IV-substituted 4,6-dinitroindoles.17... 

Furazan and furoxan sulfides and sulfones have been reported. The sulfides, formed by displacement of nitro from nitrofuroxans by thiophenols, can be oxidized to the corresponding sulfones using hydrogen peroxide. 

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