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[5]Helicenes by tandem radical cyclisation

✍ Scribed by David C. Harrowven; Michael I.T. Nunn; David R. Fenwick

Publisher
Elsevier Science
Year
2002
Tongue
French
Weight
115 KB
Volume
43
Category
Article
ISSN
0040-4039

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✦ Synopsis

A new and rapid approach to [5]helicenes is described. A central feature is the use of a sequential, non-reducing radical cyclisation reaction of (Z,Z)-1,4-bis(2-iodostyryl)benzene derivatives, viz. 31, mediated by tributyltin hydride.

πŸ“œ SIMILAR VOLUMES

[5]Helicenes by iterative radical cyclis
[5]Helicenes by iterative radical cyclisations to arenes
✍ David C Harrowven; Michael I.T Nunn; David R Fenwick πŸ“‚ Article πŸ“… 2002 πŸ› Elsevier Science 🌐 French βš– 61 KB

The paper describes a synthesis of 1,2,3,12,13,14-hexamethoxy[5]helicene 1. The synthesis features two sp 2 -sp 2 bond forming reactions, each involving a 6-exo/endo-trig cyclisation of an aryl radical intermediate to an arene.

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