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Preparation of α,α-Dibromocyclobutanones from Olefins: A simple procedure for the regioselective functionalization of olefins

✍ Scribed by Hélène Chaumeil; Claude Le Drian

Publisher
John Wiley and Sons
Year
1996
Tongue
German
Weight
548 KB
Volume
79
Category
Article
ISSN
0018-019X

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✦ Synopsis

Dibromoketene is prepared by in-situ Zn dehalogenation of tribromoacetyl bromide in the presence of POC1,. Under these conditions, the cycloaddition of dibromoketene with olefins 5 yields a,&-dibromocyclobutanones 2, which are cleaved with alkoxides to yield@-dibromomethyl esters 4. Several examples are given. For monosubstituted olefins, the functionalization is regioselective, the methoxycarbonyl group being introduced at the terminal C-atom. ') For a preliminary communication, see [l].

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