کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1314143 | 975947 | 2011 | 12 صفحه PDF | دانلود رایگان |

Difluoroallylation of optically pure O-silylated (S)-2-methyl-3-hydroxypropanal 10a with bromodifluoropropene mediated by indium provided the corresponding difluorohomoallyl alcohol 11a with low diastereoselectivity, but without a decrease in optical purity. Defluorinative allylic alkylation of each diastereomer of the difluorohomoallyl alcohol efficiently proceeded by the reaction with trialkylaluminium and Cu(I) system or Grignard reagent and a catalytic amount of CuI system in THF to give the fluorine-substituted allylic alcohol 12 in an high yield and in an excellent Z selective manner. Subsequent imidate Claisen rearrangement of the allylic alcohol 12 proceeded with a complete 1,3-chirality transfer to give the fluoroalkene dipeptide isostere structure 14 after the final conversion of the primary alcohol 20 into the carboxylic acid form.
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► High yield and highly Z selective allylic alkylation reaction of difluorohomoally alcohol derivatives with Grignard reagents and CuI catalyst leading to fluoroallyl alcohol derivatives.
► Complete 1,3-chirality transfer in the imidate Claisen rearrangement of the above fluoroallyl alcohol derivatives.
► A convienient method for the preparation of (Z)-fluoroalkene dipeptide isosteres in optically pure form.
Journal: Journal of Fluorine Chemistry - Volume 132, Issue 5, May 2011, Pages 327–338