A synthesis of γ-trifluoromethyl α,β-unsaturated γ-butyrolactones using CF(3)SiMe(3) as a trifluoromethylating agent.
نویسندگان
چکیده
A general synthesis of γ-trifluoromethyl α,β-unsaturated γ-butyrolactones is described. The fluoride-catalyzed nucleophilic addition of a trifluoromethyl (CF3) group generated from (trifluoromethyl)trimethylsilane (CF3SiMe3, Ruppert-Prakash reagent) to a masked maleic anhydride 1 (cyclopentadiene-maleic anhydride adduct) provides the corresponding adducts 2 with high stereoselectivity. The γ-trifluoromethyl α,β-unsaturated γ-butyrolactones 4 were obtained after treatment of the adducts 2 with Grignard reagents, followed by flash-vacuum pyrolysis.
منابع مشابه
Convenient synthesis of α,β-unsaturated γ-butyrolactones and γ-butyrolactams via decarboxylative iodination of paraconic acids and β-carboxyl-γ-butyrolactams using 1,3-diiodo-5,5-dimethylhydantoin.
A convenient synthetic approach to α,β-unsaturated γ-butyrolactones and α,β-unsaturated γ-butyrolactams is developed. The reaction proceeds via decarboxylative iodination of paraconic acids and β-carboxyl-γ-butyrolactams, employing 1,3-diiodo-5,5-dimethylhydantoin (DIH) under irradiation, followed by dehydroiodination of β-iodo-γ-butyrolactones and γ-butyrolactams providing good yields of α,β-u...
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 11 38 شماره
صفحات -
تاریخ انتشار 2013