separation of thp f labeled ethers from organic side products the recyclable fluorous thp tag or protecting group enables simple purification of small molecules by liquid liquid extraction with fc 72 mecn and of larger or more polar molecules by solid phase extraction with fluorous reverse phase silica gel in another aspect the present invention provides a recyclable fluorous vinyl ether tagging or protecting group that is attached and removed under mildly acidic conditions a representative example of the synthesis of a fluorous vinyl ether tagging compound is illustrated in fig3 the synthesis of vinyl ether 23 begins with commercially available iodide 21 formation of the grignard reagent from 21 was effectively accomplished with sonication for the reaction initiation thus treatment of an ether suspension of excess magnesium powder with 0 1 equivalents of 21 sonication for 20 minutes and subsequent addition of an additional 2 4 equivalents of 21 in et 2 o provided the grignard reagent after a two hour reflux period dropwise addition of one equivalent of ethyl formate to the reaction mixture and further refluxing for 5 h gave the crude fluorous alcohol 22 after standard workup this compound was conveniently purified by washing the crude solid with dichloromethane to give a 93 yield of 22 vinylation see faulkner d j petersen m r j am chem soc 1973 95 553 of 22 with 0 5 equivalents of mercuric acetate in a 1 1 mixture of ethyl vinyl ether and fc 72 at 45 u00b0 c for 40 h gave fluorous vinyl ether tagging compound 23 in 51 yield with 42 recovered alcohol 22 88 yield based on recovered starting material the extremely apolar 23 could be isolated by filtration of the crude product mixture through a short.