کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1314130 1499338 2014 15 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Synthesis of 5-alkyl-3,4-difluorofuran-2(5H)-ones by lactonisation. Effects of substituents on cyclisation ability of fluorinated 4-hydroxyalkanoates. DFT calculations of the cyclisation energies
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
Synthesis of 5-alkyl-3,4-difluorofuran-2(5H)-ones by lactonisation. Effects of substituents on cyclisation ability of fluorinated 4-hydroxyalkanoates. DFT calculations of the cyclisation energies
چکیده انگلیسی


• The synthesis of 5-alkyl-3,4-difluorofuran-2(5H)-ones was developed.
• The first synthetic step was radical addition of ethers to 2,3,3-trifluoroacrylate.
• The effects of alkyl and fluoro substituents on lactonisation were studied.
• DFT calculations of the cyclisations of 4-hydroxyalkanoates were carried out.
• Cyclisations became more feasible with increasing number of alkyls at C5.

5-Alkyl-3,4-difluorofuran-2(5H)-ones were synthesised starting with radical addition of ethers to methyl 2,3,3-trifluoroprop-2-enoate, followed by alkyloxy bond cleavage, acid-catalyzed lactonisation and dehydrofluorination. For a study of substituent effects on lactonisation, methyl 4-bromo-2-chloro-2-fluorodecanoate and 2-chloro-2-fluoro-4,4-dimethoxybutanoate based on radical additions of methyl 2-bromo-2-chloro-2-fluoroacetate to oct-1-ene or vinyl acetate were prepared. DFT calculations of the transition state energies of the exo-trig cyclisations confirmed the observation that the ring closure became more feasible with increasing number of alkyls at C4 of the fluorinated 4-hydroxyesters.

The synthesis begins with radical addition of ethers to trifluoroacrylate, followed by ether bond clavage to form 4-hydroxyalkanoates, which cyclise under strong acid catalysis and afford the butenolides by dehydrofluorination.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Fluorine Chemistry - Volume 162, June 2014, Pages 45–59
نویسندگان
, , , , ,