Intramolecular trapping of difluoroalkyl radicals by tethered olefin in the asymmetric synthesis of 2,4-disubstituted-3,3-difluorotetrahydrofurans
                                
                                    
                                        作者:Giancarlo Cavicchio、Valeria Marchetti、Alberto Arnone、Pierfrancesco Bravo、Fiorenza Viani                                    
                                    
                                        DOI:10.1016/s0040-4020(01)80890-5
                                    
                                    
                                        日期:1991.11
                                    
                                    Optically pure propenyl ethers of 3-sulphenyl-, 3-sulphinyl-, and 3-sulphonyl-1-chloro-1,1-difluoropropan-2-ols were submitted to radical cyclization affording, with moderate to high diastereoselectivity, 3,3-difluorotetrahydrofurans containing in 2 and 4 positions various substituents.  Detailed NMR analysis allowed to measure trans/cis ratios and to establish the structure of the products.