Joseph G. Atkinson

The synthesis of a leukotriene with SRS-like activity

Abstract The synthesis and biological characteristics of an SRS-like leukotriene are described.

A new synthesis of 1,2,4-benzothiadiazines and a selective preparation of o-aminobenzenesulphonamides

Reaction of a series of aniline derivatives with chlorosulphonyl isocyanate followed by cyclisation of the resulting chlorosulphonylureas with Lewis acids gives good yields of 2H-1,2,4-benzothiazidazin-3(4H)-one 1,1-dioxides. These, upon acid hydrolysis, yield the corresponding o-aminobenzenesulphonamides.

Nucleophilic displacement of activated aryl triflates a new synthesis of oxindoles and arylacetic acids

Abstract 2-Nitroaryl triflates undergo efficient base-catalyzed nucleophilic displacement by dimethyl malonate anion to yield dimethyl nitroarylmalonates, which subsequently are converted in high yields to nitroarylacetic acids and oxindoles.

A general non-reductive method for the desulfenylation of 3-indolyl sulfides

Abstract In trifluoroacetic acid, in the presence of thiosalicylic acid as a trapping agent, 3-indolyl sulfides bearing a wide variety of substituents are smoothly and rapidly desulfenylated to the corresponding 3-unsubstituted indoles.

Unexpected acid-catalysed rearrangement of certain 3-(arylthio)indoles to 2-(2-aminophenyl)benzothiophenes

3-(Arylthio)indoles (1), in which the aryl group is an electron-rich ring system, undergo a novel structural rearrangement to 2-(2-aminophenyl)benzothiophenes (2) upon heating in polyphosphoric acid.

A New Chemical Method to Desulfenylate Indol-3-yl Sulfides

Abstract Desulfenylation of indol-3-yl sulfides liberates the most reactive position of the ring for further transformations. The usual procedure, utilizing Raney Nickel (P. G. Gassman, et. al., J. Am. Chem. SOC. 1974,96, 5495) offers a limited scope due to incompatibility of a number of functional groups towards the reducing agent. Based on our recent mechanistic studies of the acid-catalysed rearrangement of indol-3-yl sulfides to indol-2-yl sulfides (P. Hamel, et. al., Chem. Commun. 1989, 63; J. Org. Chem. 1992, 57, 2694), we have developed a novel, non-reductive desulfenylation method which permits easy access to 3-unsubstituted indoles bearing a wide array of substituents. Thus, 3-indolyl sulfides, readily obtained from appropriate phenylhydrazines (via Fischer indolization) or anilines (Gassman method, vide infra) are smoothly desulfenylated in good yields in trifluoroacetic acid in the presence of an appropriate nucleophilic trapping agent. Thiols proved to be very effective trapping agents and thi...

First successful substitution of 5H-dibenzo[a,d]cyclohepten-5-one

Reaction of 5H-dibenzo[a,d]cyclohepten-5-one (1) with chlorosulphonyl isocyanate (2) results in the unexpected introduction of a carbon substituent at the 4-position of (1), through an assisted electrophilic substitution.

Acid-catalysed isomerization of indol-3-yl sulphides to indol-2-yl sulphides: unexpected intermolecular nature of the rearrangement

The rearrangement of indol-3-yl sulphides (1) to indol-2-yl sulphides (4), catalysed by proton acids, unexpectedly proceeds by an intermolecualr mechanism involving initial disproportionation to an indole-2,3-diyl bis-sulphide (2) and an indole (3), followed by a reaction between (2) and (3) to yield the rearranged product (4).