Thiobenzoyl Isocyanates Research Articles

Facile synthesis of 2-azaazulenes from thiobenzoyl isocyanates using trimethylsilyldiazomethane

The reaction of trimethylsilyldiazomethane with thiobenzoyl isocyanates, in situ generated from thiazole-4,5-diones, yielded diazoketones, which were converted into 2-azaazulenes by the intramolecular Buchner reaction.

Chlorosulfonation of Some Aldimine-Isocyanate Cycloadducts

Attempts to chlorosulfonate 1,4-diphenyl-1,3-diazetidin-2-one (1) failed, but the 3-methyl derivative (2) reacted with chlorosulfonic acid to give the bis-sulfonyl chloride (3), characterized as the sulfonamides 4 and 5. 2,3,6-Triphenyl-2,3-dihydro-1,3,5-thiadiazin-4-one (6) with chlorosulfonic acid suffered an acid-catalyzed ring-opening reaction forming the sulfonyl derivatives (8, 9) of N-phenyl-N′-thiobenzoylurea (7). Condensation of 8 and 9 with diethylamine afforded the diethyl-sulfonamide (10). Dibenzylideneethylenediamine (11) reacted with thiobenzoyl isocyanate at room temperature to yield the cycloadduct 12; however at 90°C, N,N′-di (thiobenzoylcarbamoyl)ethylenediamine (13) was obtained. The cycloadduct 12 with chlorosulfonic acid gave the ring-opened disulfonyl chloride 14 and the diethylsulfonamide 15. 1,6-Diphenylhexahydro-s-triazine-2,4-dione (17) was converted into the dimethyl derivative (18), which with chlorosulfonic acid afforded the bis-sulfonyl chloride (19), characterized as the sulfonamides 20–22. Thanks are due to the British Technology Group (BTG, Biosciences Division) for the award of a research grant (SF); Dr. Richard A'Court (BTG) for his support and interest in the project; Glaxo Group Research for the microanalyses; Smith Kline Beecham for the FAB mass spectra.

CHLOROSULFONATION OF SOME CRISSCROSS CYCLOADDUCTS FROM ISOCYANATES AND DIARYL AZINES

Reaction of chlorosulfonyl isocyanate (1) with arylaldehyde azines (7) gave the 2:1 crisscross adducts (8);attempts to prepare a disulphonamide of 8a gave only a mixture of the monosulfamide 9 and the diureide 10. The latter with trichloromethanesulfenyl chloride afforded the derivative 12a. and with chlorosulfonic acid hydrazinodicarbonamide (11). The azine 7a with benzoyl isocyanate (2) gave the expected crisscross adduct 13. With thiobenzoyl isocyanate (3) however, both 7a and 7d gave the 1: 1 adducts (14). whereas 7c gave a different 2: 1 adduct (15). Treatment of 14a with 1 gave the ureide 16. With both methyl isocyanate (4) and phenyl isocyanate (S), 7a gave the expected crisscross adducts (17a and b), and 7c with 5 similarly gave 17c. When 7a was treated with 1 followed by aqueous potassium iodide, the diureide (10) was formed; concentrated nitric acid converted 10 into the triazolenone (18). Treatment of 18 with chlorosulfonic acid-thionyl chloride gave the sulfonyl chloride (19) which was characterised as the sulfonamides (20 a-d). Diarylsulfamoyl azines (21 a-f) with 1 and potassium iodide, gave the diureides 22 a-f. 4-Methoxy-3-sulfamoylbenzaldehydeazines (23 a-c) reacted with 3 to give the 1: I adducts 24 a-c, while 4-chlorosulfonylphenyl isocyanate (6) with benzaldehyde azine (7a) gave the bis-chlorosulfonyl adduct (25a). characterised as the diethylsulfonamide 25b. Attempted chlorosulfonation of the tetraphenyl cycloadduct 17b did not give the tetrasulfonyl chloride (although the reaction was successful with the more reactive rnethoxy adduct 17c); the tetrasulfonyl chloride (26a) was converted into 3 sulfonamides (26 b-d). The unsymmetrically-substituted diaryl azines (27) reacted with 1 and potassium iodide to yield the diureides 28 a-f. Analogous cycloadditions of 1 with several keto azines were unsuccessful. Selected compounds will be screened for medicinal and pesticidal activity; compounds 9,10 and 12a showed fungicidal activity against barley powdery mildew.

Reaction of Thiobenzoyl Isocyanates with Trimethylsilyl Cyanide

Reaction of Thiobenzoyl Isocyanates with Trimethylsilyl Cyanide

Studies of Enamines. VIII. Reactions of Enamino Ketones with Benzoyl and Thiobenzoyl Isocyanates

Abstract The reaction of enamino ketone 1, derived from acetylacetone, with benzoyl isocyanate (4) gave the isomeric benzoylcarbamoyl derivatives 6 and 9, and/or 2-pyridone 7, depending upon the reaction conditions. Similarly, enamino ketone 2, derived from benzoylacetone, reacted with 4 to afford the isomeric benzoylcarbamoyl compounds 12, 13, and/or 2-pyrone 14. It has been found that the carbamoyl compound 12 was thermally converted into 13 and 14. Enamino ketones 1 and 2 reacted with thiobenzoyl isocyanate (5) at room temperature to yield the 2-pyridones 7 and 15, respectively. On the other hand, enamino ketones 3, derived from benzoylacetaldehyde and secondary amines, reacted with 4 to give the corresponding 2-benzoylcarbamoyl-2-penten-2-one compound 18, while in the reaction with 5, 3 gave the 1,3-thiazin-4-one 19 and/or (4+2) cycloaddut 20.

Studies of Acyl and Thioacyl Isocyanates. XIV. The Reactions of Benzoyl and Thiobenzoyl Isocyanates with Hydrazones

Abstract Benzoyl (1) and thiobenzoyl isocyanates (2) reacted with benzaldehyde arylhydrazones and methylhydrazone to give the corresponding semicarbazones as isolated products respectively. In the reactions with acetone arylhydrazones and methylhydrazone, however, the s-triazolidin-5-ones whose structures corresponded to the ring tautomers of semicarbazones, were isolated as sole products from the reaction of 1, and 2 afforded the (4+2) cycloadducts of 2 to the C=N bond of hydrazones and s-triazolidin-5-ones. It has been found that in some cases, the semicarbazones isomerize into their ring tautomers, and the isomerization obeys good first-order kinetics taking into account the equilibrium. Although 1 did not react with p-tosyl- and benzoylhydrazones, 2 easily added to both hydrazones to yield the corresponding (4+2) cycloadducts.

Novel rhodium and palladium complexes from benzoyl and thiobenzoyl isocyanates

Novel rhodium and palladium complexes from benzoyl and thiobenzoyl isocyanates

Acyl and thioacyl isocyanates. XIII. Reactions of benzoyl and thiobenzoyl isocyanates with hydrazobenzenes and further investigation of the reaction of thiobenzoyl isocyanate with phenylhydrazine

Acyl and thioacyl isocyanates. XIII. Reactions of benzoyl and thiobenzoyl isocyanates with hydrazobenzenes and further investigation of the reaction of thiobenzoyl isocyanate with phenylhydrazine

Studies of Acyl and Thioacyl Isocyanates. X. The Cycloaddition Reaction of Benzoyl and Thiobenzoyl Isocyanates with Benzaldazines

Abstract Although benzoyl isocyanates do not react with benzaldazines at room temperature, the criss-cross cycloadducts are formed if the reaction is carried out in refluxing xylene. On the other hand, thiobenzoyl isocyanate behaves quite differently toward the same azines. It reacts easily with azines at room temperature to afford to mono- or the bis(4+2) cycloadducts depending on the nature of the substituent in the azines. We found that the mono (4+2) cycloadduct can be thermally dissociated into its components. Neither benzoyl isocyanate nor thiobenzoyl isocyanate react with aromatic ketazines.

Studies of Acyl and Thioacyl Isocyanates. IX. The Cycloaddition Reactions of Benzoyl and Thiobenzoyl Isocyanates with Anils

Abstract Thiobenzoyl isocyanates react with benzylidenanilines, benzylidenalkylamines and dianils to yield the corresponding mono- and bis (4+2) cycloadducts. Benzoyl isocyanates do not react with benzylidenanilines, but they are easily added to benzylidenebenzylamine to give the (4+2) cycloadducts in good yields. Cycloaddition of these isocyanates to anils is dependent upon the basicity of the nitrogen atom of C=N bond. Neither benzoyl isocyanates nor thiobenzoyl isocyanates are added to the C=C bond of cinnamylidenanilines, but they react with the C=N bond to afford the (4+2) cycloadducts.

Studies of Acyl and Thioacyl Isocyanates. VIII. Cycloaddition Reactions of Benzoyl and Thiobenzoyl Isocyanates with Carbodiimides

Abstract The investigations of cycloaddition reactions of benzoyl and thiobenzoyl isocyanates with carbodiimides have shown that the adducts formed from benzoyl isocyanates and N,N′-dicyclohexylcarbodiimide are the corresponding (4+2) cycloadducts, and not the (2+2) cycloadducts proposed by Neidlein. The reaction of isocyanates with N,N′-diphenylcarbodiimide at 0°C gave (2+2) cycloadducts, which were thermally isomerized into the corresponding (4+2) cycloadducts. Benzoyl isocyanates reacted with N-cyclohexyl-N′-phenylcarbodiimide to give (4+2) cycloadducts of isocyanates to the cyclohexyl-N=C bond in the carbodiimide. On treatment with neutral alumina, (4+2) cycloadducts were easily isomerized into 1,3,5-triazines. Thiobenzoyl isocyanate reacted with both the N=C bonds of the carbodiimide to afford two isomeric (4+2) cycloadducts. It has been found that benzoyl isocyanates reacted with N-phenyl-N′-o-tolylcarbodiimide to yield the corresponding (4+2) cycloadducts of isocyanates to the o-tolyl-N=C bond and/or the isomeric 1,3,5-oxadiazin-6-ones, depending on the nature of the substituent in the isocyanate. Reaction paths for the formation of the product are also discussed.

Studies of acyl and thioacyl isocyanates—XI : The reactions of benzoyl and thiobenzoyl isocyanates with 2-thiazolines and 2-oxazolines

Thiobenzoyl isocyanate adds to 2-thiazoline and its 2-methyl derivative to afford the corresponding (4 + 2) cycloadducts. Reaction of benzoyl isocyanate with 2-methylthiazoline gives 2,3-dihydro-5-phenyl-8-benzoylcarbamoylthiazolo[3,2-c]pyrimidin-7-one. Thiobenzoyl isocyanate reacts with 2-methyl-2-thiazoline and -2-oxazoline at 90° to form the corresponding 8-thiobenzoylcarbamoylthiazolo- and -oxazolo[3,2-c]pyrimidin-7-ones, while reaction of benzoyl isocyanate with 2-methyloxazoline affords a 2:1 adduct, which with acetic acid gives the corresponding oxazolo[3,2-c]pyrimidine. Benzoyl isocyanate reacts with 2-ethyl-2-thiazoline to afford 2,3-dihydro-6-benzoyl-8-methylthiazolo[3,2-c]pyrimidine-5,7-dione and 2,3-dihydro-5-phenyl-8-methylthiazolo[3,2-c]pyrimidin-7-one; their acid and alkaline hydrolyses are described. Formation of these products is shown to proceed via attack of both isocyanates on the β-carbon of the tautomeric enamines of 2-alkyl-2-thiazoline and -2-oxazoline.

Reactions of group IV organometallic compounds: XVIII. The addition reaction of thiobenzoyl isocyanate with group IV (organometallyl)amines

Thiobenzoyl isocyanate forms 1 1 adducts with trimethylsilyl-, -germyl-, and -stannyldialkylamine. In the adducts from the silyl and germylamines, the trimethylmetal group can migrate between an oxygen and nitrogen atom. On the other hand, the adduct from the stannylamine prefers the S-metallated structure, which is consistent with the “softer” acid character of the tin compared with the silicon or germanium atom. The existence of intramolecular coordination of carbonyl oxygen with the trimethyltin group in a six-membered cycle structure, is suggested.

Studies of thiobenzoyl isocyanate—I : Reaction of thiobenzoyl isocyanate with hydrazines

The reaction of thiobenzoyl isocyanate with hydrazines is reported. With hydrazine hydrate, 4 H-5-phenyl-1,2,4-triazole-3(2 H)-one was obtained in a good yield. In the reaction with mono-substituted phenylhydrazines, 2,3-dihydro-2-aryl-5-phenyl-1,2,4-triazole-3(1 H)-one or 3-hydroxy-1-aryl-5-phenyl-1,2,4-triazole, or both were formed: the relative amount of the triazoles depended on the nature of the substituents. The reaction with 2,4-dinitrophenylhydrazine, however, gave the semicarbazide which, when treated with aqueous sodium hydroxide or polysphosphoric acid, suffered no ring closure to the triazole. Benzoyl isocyanate reacted with benzylhydrazine, yielding the same triazolone as that obtained from the reaction of thiobenzoyl isocyanate with the hydrazine. The products from these reactions have been identified by independent synthesis as well as IR and UV spectra.

Dipolar Cycloaddition Reaction of Benzoyl and Thiobenzoyl Isocyanates

Dipolar Cycloaddition Reaction of Benzoyl and Thiobenzoyl Isocyanates