Synlett 2004(10): 1723-1726  
DOI: 10.1055/s-2004-829557
LETTER
© Georg Thieme Verlag Stuttgart · New York

Indium(III) Bromide-Catalyzed Chemioselective Dimerization of Vinylarenes

Clovis Peppe*, Ernesto Schulz Lang, Fabiano Molinos de Andrade, Liérson Borges de Castro
Departamento de Química, Universidade Federal de Santa Maria-UFSM, Campus UFSM, Santa Maria, RS - 97105-900, Brazil
Fax: +55(55)2208031; e-Mail: peppe@quimica.ufsm.br;
Further Information

Publication History

Received 3 March 2004
Publication Date:
15 July 2004 (online)

Abstract

Indium(III) bromide catalyzes the dimerization of α-substituted vinylarenes. Chemioselectivity towards open chain or cyclic dimers depends on the nature of the substituent at the aryl group of the vinylarene.

    References

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  • 2a

    For H3PO4 see ref. [1]

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  • 4 Tsuchimoto T. Kamiyama S. Negoro R. Shirakawa E. Kawakami Y. Chem. Commun.  2003,  852 
5

The vinylarenes were prepared from the corresponding methyl aryl ketone upon reaction with an equimolar amount of CH3MgI in anhyd Et2O to generate the corresponding 1-aryl-1-methyl-ethanol, which was dehydrated with p-toluenesulfonic acid in anhyd benzene.