Thio phenol

Me3SiCH2CH=CH2, TsOH, CH3CN, 70-80°, 1-2 h, 90-95% yield. " This silylating reagent is stable to moisture. Allylsilanes can be used to protect alcohols, phenols, and carboxylic acids there is no reaction with thio-phenol, except when Cp3S03H is used as a catalyst. The method is also applicable to the formation of r-butyldimethylsilyl derivatives the silyl ether of cyclohexanol was prepared in 95% yield from allyl-r-butyl-dimethylsilane. Iodine, bromine, trimethylsilyl bromide, and trimethylsilyl iodide have also been used as catalysts. Nafion-H has been shown to be an effective catalyst. ... 

An 5-(l-m-nitrophenyl-2-benzoyl)ethyl thioether was used to protect thio-phenols during electrophilic substitution reactions of the benzene ring. ... 

Substituted TMM complexes also cycloadd to aldehydes in the presence of a tin cocatalyst such as MesSnOAc and MesSnOTs [31]. Reaction of 2-heptenal with methyl precursor (6) gave a mixture of methylenetetrahydrofurans (68) and (69). This regioselectivity is reversed with 10-undecenal and methyl precursor (5), where adduct (70) now predominates over (71). As in the carbocyclic system, the phenylthio group also functions as a regiocontrol element in reaction with cyclohexyl aldehyde. The initially formed adduct (72) eliminates the element of thio-phenol on attempted allyl rearrangement, and the overall process becomes a cycloaddition approach to furans (Scheme 2.21) [20]. 

More recent prepns are by the reaction of tetra-fluorohydrazine (F2NNF2) with thio phenol, yield up to 74% (Ref 7) by treatment of tri-phenylmethyldifluoramine with sulfuric acid, yield almost quant, purity by mass spec 99%... 

Auf diese Weise konnen auch aromatische Amine iiber die Diazoniumsalze in Thio-phenole iibergefiihrt werden1,3. 

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) ... 

Neilson AH, C Lindgren, P-A Hynning, M Remberger (1988) Methylation of halogenated phenols and thio-phenols by cell extracts of Gram-positive and Gram-negative bacteria. Appl Environ Microbiol 54 524-530. 

Allyl p-tolyl sulphoxide 535 reacts with sodium methoxide in methanol by initial prototropic isomerization and subsequent addition of methanol to give 536 (equation 333). Protic solvents are photochemically incorporated by the open chain olefinic bond of trans methyl )S-styryl sulphoxide 537 in a Markovnikov regiospecificity (equation 334). Mercaptanes and thiophenols add to vinyl sulphoxides in a similar manner (compare also Reference 604 and Section IV.B.3) to give fi-alkylthio(arylthio)ethyl sulphoxides 538 (equation 335). Addition of deuteriated thio-phenol (PhSD) to optically active p-tolyl vinyl sulphoxide is accompanied by a low asymmetric a-induction not exceeding 10% (equation 336) . Addition of amines to vinyl sulphoxides proceeds in the same way giving )S-aminoethyl sulphoxides in good to quantitative yields depending on the substituents at the vinyl moiety When optically active p-tolyl vinyl sulphoxides are used in this reaction, diastereoisomeric mixtures are always formed and asymmetric induction at the p- and a-carbon atoms is 80 20 (R = H, R = Me) and 1.8 1 (R = Me, R = H), respectively (equation 337) ... 

This technique eliminates the long induction period at 0° and the violent foaming described in the preparation of thio-phenol.8 However, in a larger-scale operation it would be advisable to check the rate of addition of the zinc dust somewhat, lest an exception arise. 

Method A The glucopyranosyl bromide (1 mmol) in CH2C12 (10 ml) and HzO (10 ml) is added to the phenol (3 mmol) and TEBA-C1 or Adogen (0.2 mmol) in aqueous KOH or NaOH (25 mmol) and the mixture is stirred at room temperature for 8-60 h. The organic phase is separated, washed with H20, dried (MgS04), and evaporated to yield the O-aryl derivative (68% from phenol 60% from 2-cresol 53% from 3-chlorophenoI, 54% from 4-methoxyphenol 56% from 4-nitrophenol 57% from 1-naphthol 44% from thio-phenol 36% from 8-hydroxyquinoline). 

Even if the extraction of FeMoco in nmf slightly modifies the outer coordination of the MoFe7S9 cluster, in agreement with the experimental observation that the FeMo-protein can exist in the oxidized, semi-reduced and reduced forms, it exhibits two successive one-electron reductions (E st = -0.32 V and is d = -1.00 V,vj. NHE). In the absence of thio-phenol, the first reduction appears to be complicated by self-oxidation processes, whereas the presence of thiophenol apparently stabilizes the different oxidation states. 

Where it is possible to distinguish the products, thiol additions show stereospecificity. The products of addition of hydrogen sulfide, thio-phenol, and thiolacetic acid to 1-chlorocyclohexene are to be 75%, 94%, and 66% cis-l, 2-disubstituted cyclohexane, respectively.88 The addition of thiolacetic acid is less stereopecific than the other thiols. The stereospecificity apparently depends upon the ratio of addendum to 1-chlorocyclohexene, Phenylthiyl radical addition to 1-methylcyclo-... 

Photolysis of aryl-desyl sulfides (LV, It = C H6) yielded didesyl (LVII).240 Desylthiobe n zoate (LV, R = SCOC6H6) gave didesyl and dibenzoyl disulfide. It is probable that in the former case the phenylthiyl radical (C0H6S ) abstracts hydrogen from the solvent to give thio-phenol and that in the latter reaction dibenzoyl disulfide is formed from the dimerization of benzoylthiyl radical (C H6COS-). The formation of LVII may be attributed to the dimerization of the desyl radical (LVI). O OH... 

Asymmetric Michael addition.1 The highest optical yield for addition of thio-phenol to maleates is obtained with diisopropyl maleate catalyzed by cinchonine (equation I). The succinate obtained in this way was used for synthesis of (R)-( + )-3,4-epoxy-l-butanol. 

These are generally liquids with an unmistakable penetrating, disagreeable and characteristic odour, which persists even at extremely low concentrations in air. Alkanethiols are partly soluble in concentrated solutions of sodium hydroxide but their salts are hydrolysed to the free thiols on dilution with water. Thio-phenols are soluble in sodium hydroxide solution but like the alkanethiols do not evolve carbon dioxide from sodium hydrogen carbonate solution. Treatment of a dry thiophenol with sodium results in the evolution of hydrogen (cf. Alcohols, Section 9.5.3, p. 1223). 

The neutral sulphur compounds include sulphides or thioethers, disulphides, sulphoxides and sulphones, sulphate and sulphonate esters, and isothiocyanates. Acidic sulphur compounds, i.e. sulphonic and sulphinic acids, thiols and thio-phenols, and the primary sulphonamides have already been discussed. The sulphates of amines are converted by aqueous sodium hydroxide into the free bases the sulphate anion can be detected in the resulting aqueous solution as barium sulphate in the usual manner. 

Conditions were found under which 2,4,6-trinitrostyrene adds nucleophiles (thio-phenol, aniline, and aliphatic amines) at the vinyl moiety to form the corresponding / -X-ethyl-2,4,6-trinitrobenzenes (X = PhS, PhNH, or R2N). In the reactions with primary aromatic amines, the initially formed adducts undergo an intramolecular replacement of the nitro group followed by aromatization of the indolines, giving rise to the corresponding A-substi Luted 4,6-dinitroindoles.219... 

It is assumed that phenols can conjugate directly with D-glucuronic acid or sulfuric acid. The scheme explains why phenols do not conjugate with mercapturic acid. Parke and Williams128 have recently shown that administration of phenylmercapturic acid or phenylcysteine to the rabbit is followed by the excretion of phenylcysteine, ester sulfates, and thio-phenol, and phenylcysteine also yields diphenyl disulfide. The thiol donor... 

Thiol Decomposition. As explained previously, the elimination of sulfur from benzothiophene occurs stepwise after the aromatic thiol (o-thiocresol) has formed and not in a concerted fashion from the thiophenic ring system. Extrapolation of this implies that thio-phenic sulfur in coal is eliminated by conversion to an aromatic thiol that subsequently undergoes desulfurization. Since the aromatic thiol is the apparent organosulfur species that undergoes desulfurization, it is of interest to understand the chemistry involving the elimination of sulfur from aromatic thiols. Thio-phenol was used as a model compound to examine reactions, primarily the thermal decomposition reactions that might lead to sulfur elimination. In the experiments with caustic and benzothiophene, the intermediate (o-thiocresol) most likely exists in the salt... 

Since thiophenol is a moderately strong acid, it was expected that potassium and sodium salts of thiophenol would be present in the molten KOH-NaOH mixture. Both the sodium and potassium thio-phenolate salts were prepared in order to examine their thermal stability. Reaction products with the neat sodium salt were essentially the same as with thiophenol. Only diphenylsulfide (<1J) and diphenyldisulfide (1J-3.5J) were found, along with recovered starting material. Results using the neat potassium salt of thiophenol were completely different. The potassium salt underwent substantial decomposition (Equation 9), producing benzene (25 -3050 as the major identifiable product, 36 -38 CH2Cl 2-insoluble material, and 11 -15 recovered thiophenol (as unreacted potassium salt). 

Phosphate ester cleavage can also be achieved with artificial enzymes using both a metal ion and an additional catalytic group, as in the amide and ester hydrolyses described above. In our first example, catalysts 32 and 33 combined a Zn2+ with a thio-phenol and an imidazole group respectively [121]. The rigid structure prevented the... 

The method has proved to be valuable for the synthesis of basic thio-phenols in industrial synthesis, as shown by the manufacture of the starting material dimethylthiocarbamoyl chloride [104]. 

The electrochemical reversibility of the M(VI)/M(V) couple for the complexes with sterically hindered ligands contrasts with the reported behavior of the [MoO(SPh)4] complex, which exhibited electrochemical irreversibility for the Mo(V)/Mo(VI) step but a reversible Mo(IV)/ Mo(V) couple. The sterically hindered aromatic substituent groups stabilize the molybdenum(VI) complex and decrease relative to the thiophenol derivative. The molybdenum(VI) species can also be isolated by chemical oxidation. [MoO(PFTP)4] was prepared by chemical redu-tion of [MoO(PFTP)4] . The presence of the electron-withdrawing substituents on the aromatic thiolate increases E ei relative to the thio-phenolate derivative. Evidently the properties of these last complexes are influenced primarily by the electron-withdrawing characteristics of the fluorine substituents rather than by steric factors (33). 

Brede O, Ganapathi MR, Naumov S, Naumann W, Hermann R. (2001) Localized electron transfer in nonpolar solution Reaction of phenols and thio-phenols with free solvent radical cations. /Phys Chem A 105 3757-3764. 

R = H, Me, Ph, 2-pyridyl NuH = nitrogen heterocycles, (thio)phenol, secondary amines... 

Chem. Soc. 63, 1609 (1941). Solubility possible H bonding of phenylacetylene, thio-phenol in ketones, esters, etc. 

It seems that the stabilizing effect of the double bond on the electronic charge on sulfur (in isobutenyl sulfide) overrides the normal C-S cleavage reaction and thio-phenol may be formed in an intramolecular process. In quinoline solution the thermolysis proceeds at lower temperatures to yield thiachromane and thiacouma-rane the role of the amine solvent has been discussed but lies outside the scope of this review. 

Sulphur Compounds.—The two preceding reactions with water and with alcohol may be carried out also with the analogous sulphur compounds, viz., hydrogen sulphide, H—SH, and thio-alcohols or mercap-tans, e.g.j C2H6—SH. The product in the first case is a thio-phenol, CeHs—SH, and in the second phenyl ethyl thio-ether, CeHs—S—C2H6. 

---