Fluorinated cyclopropanes

This paper reviews the synthetic methods for functionalized fluorinated cyclopropanes with an emphasis on asymmetric syntheses. These are (1) the Simmons–Smith reaction of fluoroallyl alcohol derivatives, (2) difluorocarbene addition to chiral olefins, (3) utilization of 4-bromo-4,4-difluorocrotonate as a building block, and (4) preparation of methylenedifluorocyclopropanes. Some applications to the syntheses of fluorine-modified amino acids are also described.