Sodium thiobenzoate

Historically, this represents the first thiophene synthesis, when Laurent obtained tetraphenylthiophene by heating polymeric thiobenzaldehyde in 1844. Almost any aromatic methyl derivative can be converted to tetraphenylthiophene, which is thermodynamically the most stable thiophene, by heating with sulfur. Toluene, phenylacetic acid, benzyl alcohol, benzyl sulfide or disulfide, benzyl sulfonate or even sodium thiobenzoate have been converted to tetraphenylthiophene under these conditions (52HC(3)l). 

Millan and co-workers studied the substitution reaction of PVC with sodium thiobenzoate [43], sodium-2-mercaptobenzothiozolate [44] and the substitution reaction is confirmed by IR spectra. The presence of bands at 757 and 727 cm1 for 2-mercaptobenzothiazolate and bands at 653, 690 and 775 cm"1 for thiobenzoate along with 615 and 637 cm 1 for C-Cl indicate that substitution has taken place. 

Vanadium oxodichloride VOCI2 reacts with sodium thiobenzoate and potassium l,l-bis(thiooxalate) in an aqueous solution to give the corresponding... 

Only the green crystals of the chromium tris(thiobenzoato) complex Cr(PhCOS)3 21 have been obtained, by the stoichiometric reaction of CrCl3 6H20 with sodium thiobenzoate in aqueous conditions [73,271]. Like many other Cr(III) complexes, the complex 21 is a monomer in which the three thiobenzoato ligands bind to the metal in chelate mode. 

It is well-known that the reaction of palladium(II) acetate with an excess of thiobenzoic acid in benzene gives the polymeric thiobenzoato palladium complex 51 [Pd(PhCOS)2]x (x>3) [83], although the complex formed from the reaction of PdCl2 with sodium thiobenzoate in water was reported to be dimeric [Pd(PhCOS)2]2 in benzene [253]. The thiobenzoato complexes 51 obtained by the reaction of Na2PdCl4 with sodium thiobenzoate react with Lewis bases to give the neutral monomeric complexes trans-Pd(PhCOS)2(L)2 (L R P, R3AS, RsSb, pyridines, and so on), where the PhCOS ligands are monodentate... 

Similar to the palladium complexes mentioned above, the complex Pt(PhCOS)2]x (55), obtained by the reaction of Na2PtCl4 with sodium thiobenzoate, also reacts with Lewis bases such as phosphines and pyridines giving the neutral mono-... 

The reactions outlined in Scheme 96 have been used to prepare 3 -thioadenosine and 9-(3-thio-P-D-xylofuranosyl)adenine. The 0,S-dibenzoate (627), one of the products formed in the displacement reaction with sodium thiobenzoate, arises from an S 0 benzoyl migration and benzoylation of the liberated 3 -thiol group. The other product isolated from this displacement reaction was 9-(2-0-benzoyl-3-deoxy-P-D- /ycero-pent-3-enofuranosyl)adenine. Hydrogenolysis of the dibenzoate (627) and a related 2 -thiobenzoate [prepared from 5, /V -dipivaloyl-9-(2-deoxy-2-iodo-P-D-arabinofuranosyl)adenine] gave 3 - and 2 -deoxyadenosine after removal of the protecting groups. 

With thiophenol in the presence of zinc chloride and hydrochloric acid, thioindoxyl-1,1-dioxide and related compounds give 3-phenyl-thiobenzo[6]thiophene-l, 1-dioxides, which afford the corresponding 2,3-dihydrobenzo[6]thiophene-l,1-dioxide on reduction with zinc and sodium hydroxide.756... 

Tellurium bis[thiolobenzoate] was obtained from sodium tellurite and thiobenzoic acid in strongly acidic medium. The compound was recrystallized from benzene. A single-crystal X-ray structural analyses showed the thiolobenzoate groups to be bidentate2. 

A reactor was charged with water (490 g), sodium dodecyl sulfate (0.56 g), acrylonitrile (8.8 g), and cumenyl thiobenzoic acid (1.09) and then heated to 80°C for 20 minutes. This solution was treated with 4,4 -azobis(4-cyanovaleric acid) (0.93 g) and additional water (25 g) and then stirred for 30 minutes. Thereafter additional acrylonitrile (45.0 g) was added dropwise over 1 hour, and the mixture heated for approximately 5 hours. A sample was taken that indicated thepolymer had aMwOf 13,700daltonsandM of 10,300daltons with a polydispersity index of 1.33. The mixture was then treated with n-butyl acrylate (20.0 g), 4,4 -azobis(4-cyanovaleric acid) (0.40 g), and water (10 g) and stirred 1 hour at 80°C. The mixture was further treated with n-butyl acrylate (80.0 g) over 2 hours and... 

The reaction of nickel chloride and thiobenzoic acid in ethanol in the presence of sodium hydroxide gave [Ni2(PhCOS)4] (91). 

Benzoyl disulfide has been obtained by the reaction of benzoyl chloride with hydrogen sulfide, hydrogen disulfide, hydrogen trisulfide, potassium sulfide, sodium disulfide, lead sulfide, sodium hydrosulfite, sodium thiosulfate, sulfhydrylmagnesium bromide, and thiobenzamide. It is also formed by reaction of benzoic anhydride with hydrogen sulfide. The better preparative methods involve the oxidation of thiobenzoic add by means of air,hydrogen peroxide or sulfur monochloride, or of the sodium or potassium salt by means of air, - chlorine, iodine, copper sulfate, - potassium ferricyanide, - or ferric chloride. - ... 

L-Arabinose diethyl dithioacetal was converted, via its 2,3-<9-isopropylidene derivative 298 and its thiobenzoate 299, into 4-azido-4-dco. y-5-lliio-a-D-xylopyranose triacetate (300).- " Ditosylation of 297, displacement of the 5-tosyloxy group by treatment with potassium thiobenzoate, and exchange of the 4-tosyloxy group with sodium azide in DMF gave the 5-az.ido-4-.S -benzoyl-D-xj lose derivative 301, isolated as the main compound (65%) via a 4,5-episulfonium intennediate. 

Thioxo-l,3-benzothiazin-4(3/f)-one (250) is formed by reacting 2-thiobenzoic acid (251) with potassium isothiocyanate alkylation of (250) with methyl iodide and sodium hydroxide yields the S-methyl derivative (252) (Scheme 47) <89Ml 607-oi>. 

Thioacetic333 and thiobenzoic acid 333,334 In a 1-1 flask fitted with a stirrer and reflux condenser, anhydrous pyridine (200 ml) is saturated by a stream of hydrogen sulfide that has been washed by iodine solution and dried through calcium chloride. It is then treated with acetyl chloride (40 g) with stirring and cooling to below 15° for 2-3 h alternatively, benzoyl chloride (40 g) is similarly added at 5°. Thereafter the mixture is acidified with the calculated amount of 5N-sulfuric acid and extracted with ether. The extract is dried over sodium sulfate and fractionated in a stream of nitrogen, giving thioacetic, b.p. 87.5-88°, or thiobenzoic acid, b.p. 85-87°/10 mm, in 60-65 % yield. 

When shaken with benzoyl chloride and an excess of sodium hydroxide solution, 1,5-pentanedithiol gives an almost quantitative yield of S jS-pentamethylene bis(thiobenzoate), m.p. 45° (after recrystallization from ethanol).336... 

Bis(thiocarboxylato) niobium 18Nb(RCOS)2 [207] and bis(r] -cyclopenta-di-enyl)bis(thiobenzoato)niobium 19 [110] have been synthesized by stoichiometric reactions of NbCl2 with sodium thiocarboxylates and of Nb(Cp)2X2 (X=C1, Br, I) with thallium thiobenzoate, respectively. The structure of 19 is considered to be analogous to the tantalum complex 20, in which the thiocar-boxylato ligands are monodentate through the sulfur atom [110]. 

Analogous to the synthesis of l,4-benzodioxepin-5-ones, the benzoxathiepinones (166) were prepared by the reaction of ethyl 2-thiobenzoates with chlorohydrin and glycerol chlorohydrin and cyclization of intermediate (165) (Scheme 17) <75BSF277>. The sodium borohydride reduction of bienzoxathiepinone (167) has also been studied <82NJC149>. 

Nucleophilic replacement reactions (by AcS, Ph CO S , MeS , and PhCHaS") with methyl 0-toluene-p-sulphonyl-L-lactate and sodium L-2-chloropropionate give 2-acylthio- and 2-alkylthio-D-propionic acids and esters. Extensive racemization accompanies the use of excess thio-acetate or thiobenzoate, due to further 5 2 replacement reactions, as observed for LiAlH4 reduction of L-(2-methylthio)propionic acid or its methyl ester. Diborane reduction gives optically pure L-(2-methylthio)-propanol, however. This work includes a new synthesis of ( + )-2-mercaptopropionic acid, though by known methods, and establishes the D configuration for this isomer. 

Preparation.—A quaternary ammonium anion-exchange resin, in its carbonate form, is the reagent in a new and convenient procedure for the hydrolysis of primary, allyl, and benzyl halides to the corresponding alcohols. A shortened (two-stage) sequence for the conversion of primary alkylamines to alcohols mediated by pyrilium salts (c/. 2,113 4,138) is outlined in Scheme l treatment of the intermediate pyridinium salt (1) with sodium 2-hydroxymethylbenzoate (or thiobenzoate) leads directly to isolation of the alcohol, rather than the esters obtained when sodium acetate or sodium trifluoroacetate are employed. 

Phase transfer catalysis has been utilized in the orrto-metallation of thiobenzo-phenone derivatives. Triiron dodecacarbonyl reacts with thiones in benzene solution in the presence of benzyltriethylammonium chloride and aqueous sodium hydroxide to give the complex shown in equation 9.17. Thiobenzophenone, 4,4 -dimethylthio-benzophenone, 4,4 -dimethoxythiobenzophenone and thio-Micheler ketone were all successfully metallated in 70%, 36%, 80% and 76% yields respectively. 

Under less vigorous conditions the acyclic monoamide (—amic acid) is formed and this can usually be converted into the cyclic imide by treatment with a mild dehydrating agent such as acetyl or thionyl chloride [77]. Alternatively, the reactants may be refluxed with triethylamine in benzene or toluene and the water formed in the reaction removed by azeotropic distillation [78]. The phthaloyl group has also been introduced into a-amino acids by heating with 0-carbethoxy-thiobenzoic acid in JV,JV-dimethylformamide at 80° [79], or at room temperature with JV-ethoxycarbonylphthalimide in the presence of sodium hydroxide [80]. 

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