The regiochemistry and stereochemistry of 1,3-dipolar cycloadditions of 1-fluoro- and 1,1-difluoroallene

Article abstract of DOI:10.1016/S0040-4020(01)81456-3

1,3-Dipolar cycloadditions of diazoalkanes, nitrones and nitrileoxides occur with high regioselectivity to 1,1-difluoroallene and fluoroallene, and with variable syn or anti π-facial diastereoselectivity with regard to additions to the latter. The roles of steric effects, frontier molecular orbital effects, electrostatic interactions and other factors which may be involved in determining the observed regioselectivity and π-facial diastereoselectivity are discussed.