Showing papers by "Marcello Tiecco published in 1977"
TL;DR: In this paper, 1-Adamantyl radicals react with several 2-substituted benzothiazoles to afford 2-(1-adamantyl)-benzothiazole as a result of a homolytic substitution occurring at the ipso position.
Abstract: 1-Adamantyl radicals react with several 2-substituted benzothiazoles to afford 2-(1-adamantyl)-benzothiazole as a result of a homolytic substitution occurring at the ipso position; the yields are greater when the groups to be displaced are electron-withdrawing.
15 citations
TL;DR: In this article, the reaction of 1-adamantyl, 3,3-dimethylbicyclo[2.2] octan-1-yl and 7,7-dimethyltimethylbicyl[2] heptan- 1-yl radicals with protonated pyridines and quinoline was investigated and the relative rates of substitution were determined.
Abstract: The reactions of 1-adamantyl (1), 3,3-dimethylbicyclo[2.2.2]octan-1-yl (2), and 7,7-dimethylbicyclo[2.2.1]heptan-1-yl (3) radicals with protonated pyridines and quinoline have been investigated and the relative rates of substitution have been determined. The results obtained showed that the three bridgehead radicals have nucleophilic properties which decrease in the order: (1) > (2) > (3). This behaviour is explained on the basis of a different degree of charge development in the transition state of the addition step of the radicals to the protonated substrates, as a consequence of different ring strain in the three polycyclic systems. A comparison of the present results with those already available for other alkyl radicals is also reported, in order to evaluate the effect of electronic configuration on the reactivity of carbon radicals in homolytic aromatic substitution.
14 citations
TL;DR: In this paper, 1-adamantyl and other alkyl radicals, produced by the AgI catalysed decarboxylation of carboxylic acids by ammonium peroxydisulphate, react with 2-acylbenzothiazoles, effecting the displacement of the acyl group to afford 2-alkyl benzothiazole in good yield.
Abstract: 1-Adamantyl and other alkyl radicals, produced by the AgI catalysed decarboxylation of carboxylic acids by ammonium peroxydisulphate, react with 2-acylbenzothiazoles effecting the displacement of the acyl group to afford 2-alkylbenzothiazoles in good yield Thereaction with 1-adamantyl radicals is facilitated by the presence of electronwithdrawing substituents in the 5- and 6-positions of the benzothiazole nucleus The displacement process is regarded as an aromatic SR reaction occurring at the ipso-position
10 citations
TL;DR: In this article nucleophilic acetyl radicals react with 2-substituted benzothiazoles effecting the displacement of several groups to afford 2-acetylbenzothiazole; the reactions are proposed to occur through a homolytic aromatic substitution at the ipso position.
Abstract: Nucleophilic acetyl radicals react with 2-substituted benzothiazoles effecting the displacement of several groups to afford 2-acetylbenzothiazole; the reactions are proposed to occur through a homolytic aromatic substitution at the ipso position.
9 citations
TL;DR: In this paper, 1-Adamantyl radicals react with several 2-substituted benzothiazoles to afford 2-(1-adamantyl)-benzothiazole as a result of a homolytic substitution occurring at the ipso position.
Abstract: 1-Adamantyl radicals react with several 2-substituted benzothiazoles to afford 2-(1-adamantyl)-benzothiazole as a result of a homolytic substitution occurring at the ipso position; the yields are greater when the groups to be displaced are electron-withdrawing.
TL;DR: In this paper nucleophilic acetyl radicals react with 2-substituted benzothiazoles effecting the displacement of several groups to afford 2-acetylbenzothiazole; the reactions are proposed to occur through a homolytic aromatic substitution at the ipso position.
Abstract: Nucleophilic acetyl radicals react with 2-substituted benzothiazoles effecting the displacement of several groups to afford 2-acetylbenzothiazole; the reactions are proposed to occur through a homolytic aromatic substitution at the ipso position.