Thiobenzoylation

Optically active thiazoline-5-ones (203) can be obtained when cycliza-tion of an optically active N-thiobenzoyl amino acid is brought about by the use of dicyclohexyl carbodiimide in pure chloroform, dich-loromethane (455), or tetrahydrofuran (453. 456) (Scheme 104). 

Mercapto-imida2oliuin inner salts have been reported to rearrange under the influence of hydrochloric acid, producing S-aminothiazolium chlorides (Scheme 25) (36). Their N-acylated derivatives are obtained by cyclization of N-thiobenzoyl alkylaminoacetonitriles, effected with acyl or sulfonyl halides (Scheme 26) (34, 35). 

A similar regiospecific [2 -I- 2] cycloaddition across a C=S group occurred when benzoyl isothiocyanate (436) and 2,3-diphenyl-1-azirine were heated in refiuxing benzene for 12 hours. The product obtained was shown to be (438) and an intermediate such as (437) could also be involved in this cycloaddition (74JOC3763). In contrast, thiobenzoyl isocyanate added in a [4-1-2] fashion, and after ring expansion gave a thiadiazepine derivative. 

The dimethylsulfonium ylide (568) added readily to aroyl isocyanates to give the intermediate addition product (569). This on heating underwent ring closure with loss of dimethyl sulfide to form the 4-hydroxyoxazole (570) (73T1983). This normal C-acylation of the sulfonium ylide also leads to thiazoles with thiobenzoyl isocyanate in this case the initial acylation product was not isolated, the thiazole being obtained directly. 

The base-catalyzed reaction of thiothreitol with methyl dithiobenzoate selectively protects a thiol group as an 5-thiobenzoyl derivative in the presence of a hydroxyl group.-... 

Acetvldiphenylsulfide is reacted with carbon disulfide in an initial step to give 4-phenyl-thiobenzoyl dithioacetic acid. That, in turn, is reacted with o-phenylenediamine. 

The azirine 1 reacts with thiobenzoyl isocyanate to give the Diels-Alder adduct 2. which at 80CC undergoes ring expansion to the thiadiazepinone 3, the only known representative of this ring system.327... 

Low molecular weight or polymeric ATRP initiators have been converted to dithiobenzoate RAFT agents by reaction with phcnylcthyl dithiobenzoate RAFT agent441,655 or by reaction with bis(thiobenzoyl) disulfides under ATRP conditions.483 It is likely that ATRP initiators can be transformed to other forms of RAFT agent by similar methods. 

Ahnlich liefert Bis-[thiobenzoyl]-disulfan 75-90% Dithiobenzoesdure bzw. 70-80% Benzylthiol2. 

Thiobenzamides can also be obtained by reaction of N-thiobenzoyl-1,2,4-triazole (D) or N-thiobenzoylbenzotriazole (E) and amines (in cyclohexane, CHC13, or acetone as solvents, at temperatures between 10 and 50 °C),[166] as indicated in Table 4-6. 

An EPR study of the monomeric 02 adducts of the Schiff base complexes of Co(bzacen)(py) (71a) and the thiobenzoyl analog Co(Sbzacen)(py) (71b) characterized the five-coordinate mono (pyridine) precursors and the six-coordinate 02 adducts.327 Increased covalency in the Co—S bonds was seen in the EPR parameters, indicative of 7r-backbonding. Substituent effects on the aromatic rings had no effect on the EPR spectra, but these were reflected in the observed redox potentials. Furthermore, the S-donors stabilize the Co ion in lower oxidation states, which was consistent with destabilization of the 02 adducts. 

The addition of thiobenzoyl isocyanate to norbornene and norbornadiene resulted in the thiazinones 230 (R = Ph) and 231, respectively (67CB685). The ter/-butyl- and mesityl-substituted analogs of 230 were prepared by the same method. In the case of a benzyl substituent, the derivative 232 containing an exo double bond was formed (81CB549). 

The urea (224) has been prepared from thiobenzoyl isocyanate and phenylhydroxylamine (Scheme... 

Formamidine disulfide (103) was also formed when 5-aminothiatriazole (10) was allowed to react with thiobenzoyl chloride in acetonitrile without addition of base (81BSB89>. Beer and Hart found that 5-aminothiatriazole (10) reacted with acetyl chloride or acetic anhydride to give 3,5-diace-tamido-l,2,4-thiadiazole (104 R = Me) while neither a thiapentalene (102) nor 5-acetamido-thi-atriazole was observed (Scheme 18) <77CC143). In contrast, L abbe and Vermeulen isolated 2,5-dimethyl-l,6-dioxa-6a-/, -thia-3,4-diazapentalene (102 R = Me) together with the 1,2,4-thiadiazole... 

A number of general methods for the synthesis of meso-ionic 1,2,4-triazol-3-ones are available. Sodium ethoxide-catalyzed cyclization of 1-benzoyl-l,4-diphenylsemicarbazide (201, R = R = R = Ph, X = O) yielded anhydro-3-hydroxy-1,4,5-triphenyl-1,2,4-triazolium hydroxide (200, R = R = R = Ph). A general route to meso-ionic 1,2,4-triazol-3-ones (200) is exemplified by the formation of the 1,4,5-triphenyl derivative (200, R = R = R = Ph) from A-amino-MA -diphenylbenzamidine (202, R = R = R = Ph) and phosgene. In contrast with this ready meso-ionic compound formation, the corresponding reaction of the iV-methylbenzamidine (202, R = Me, R = R = Ph) did not yield the meso-ionic 1,2,4-triazol-3-one (200, R = Me, R = R = Ph). The product was in fact 3,4-diphenyl-2-methyl-l,2,4-triazol-5-onium chloride (203), which on heating gave 3,4-diphenyl-1,2,4-triazol-5-one (204, R = Ph). The formation of the A-methyl derivative (200, R = Me, R = R = Ph, yield 79%) by heating the 7V-thiobenzoyl semicarbazide (201, R = Me, R = R = Ph, X = S) with potassium carbonate in methyl cyanide has been reported. Another synthesis of A-methyl derivatives (200, R = Me) involves methylation of 3-methyl-4-phenyl-l,2,4-triazol-5-one (204,... 

The reaction between iV-thiobenzoyl-A-methylhydrazine (232, R = Me, R = Ph), and phenylthioacetylthioglycolic acid, Ph-CHj-CS—S-CHj-COjH, did not yield the expected product. A deep red substance, m.p. 238°-239°, has been isolated, and its X-ray crystallographic examination has shown that it has the meso-ionic structure 264. This... 

Die Umsetzung von Thiobenzoesaure-chlorid mit Imidazol bzw. 2-Methyl-imidazol fuhrt zu 1-Thiobenzoyl- bzw. 2- Methyl-1 - thiobenzoyl-imidazol (s. Bd.E5/2, S. 1246). 

Aryl-4-arylazo-2-hydroxy-l, 3-thiazole werden durch Kupplung aromatischer Diazonium-Salze mit N-Thiobenzoyl-glycinen erhalten1 ... 

Die Addition von elementarem Schwefel an (3-Phenyl-allyliden)-malonsaure-ethylester-nitril ergibt 2-Amino-3-ethaxycarbonyl-5-thiobenzoyl-thiophen in 40%iger Ausbeute an-stelle dieser Cycloaddition kann man auch direkt Zimtaldehyd mit Malonsaure-ethylester-nitril und Schwefel umsetzen und erhalt so das Thiophen-Derivat in 64% Ausbeute2. 

The 1,3,5-thiadiazepine (559) has been prepared by the thermal rearrangement of the [4 + 2] cycloadduct (558) of the azirine (557) and thiobenzoyl isocyanate (74JOC3763). The benzoyl isocyanate adduct does not rearrange to give an oxadiazepine. 

Photolysis of 1,2,3-thiadiazole (44) gives thiirene (45) which can be trapped by an alkyne (70AHC(ll)l). 4,5-Diphenyl-1,2,3-thiadiazole (46) is photolyzed at low temperatures to the thiobenzoyl-phenylcarbene triplet (47). Diphenylthioketene (48) is formed on warming (8lAHC(28)23l). 

The nonclassical thiophenes (6), (12) and (13) show intense molecular ions (over 70%) as well as pronounced doubly charged M2+ ions. Other characteristic fragment ions result from the loss of phenyl or methyl substituents as the case may be. The thiobenzoyl fragment at m/e 121 (10-20%) is another common fragment in these molecules. The mass spectral fragmentation of tetraphenylthieno[3,4-c]thiophene (6) is presented in Scheme 6. 

The corresponding compound with thiobenzoyl diazenido ligands also has been prepared (37). 

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