CHED 326 |
| Indium is a useful metal for Barbier reactions in aqueous media, allowing for “green chemistry” C-C bond formation.. This methodology has been applied to the reaction of a,a-difluoropropargyl bromide (1) and several aldehydes (2) to obtain gem-difluoro homopropargyl alcohols (3) as the major product, in good yields, without the problem of a-defluorination. However, the drawback of this method is the cost of Indium; thus finding a cheap metal with similar effects is key to enhancing the accessibility of this methodology. Ten metals were selected by price and electron potential and screened alongside two additives. A system of In (0.1 eq.), Zn (0.9 eq.), and I2 (0.1 eq.) was found to be most cost effective, producing alcohols (3) in moderate yields and lowering the yield of dimer byproduct (4). The synthetic utility of (3) was investigated using a Lewis acid catalyzed cyclization reaction which produced the substituted furans in good yields.
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Undergraduate Research Poster Session: Organic Chemistry
2:30 PM-4:30 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Poster
Division of Chemical Education |
