A highly efficient TBAF-promoted intramolecular cyclization of gem-dibromoolefins for the synthesis of 2-bromobenzofurans(thiophenes).
نویسندگان
چکیده
A highly efficient tetra-(n-butyl)ammonium fluoride (TBAF)-promoted intramolecular cyclization of gem-dibromoolefins has been developed for the synthesis of 2-bromobenzofused heterocycles. The reaction provides a convenient approach to 2-bromobenzofurans(thiophenes) from the corresponding readily available gem-dibromovinyl substrates without a metal.
منابع مشابه
Trace amount Cu (ppm)-catalyzed intramolecular cyclization of 2-(gem-dibromovinyl)phenols(thiophenols) to 2-bromobenzofurans(thiophenes).
An intramolecular cyclization of 2-(gem-dibromovinyl)phenols(thiophenols) to give 2-bromobenzofurans(thiophenes) in the presence of a trace amount of Cu (0.0064 mol%, 25 ppm) has been developed. The reaction provides the desired products in excellent yields under fluoride-free and mild reaction conditions and with a TON (turnover number) of up to 1.5 × 10(4).
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ورودعنوان ژورنال:
- Chemical communications
دوره 47 37 شماره
صفحات -
تاریخ انتشار 2011