Separation of "light fluorous" reagents and catalysts by fluorous solid-phase extraction: Synthesis and study of a family of triarylphosphines bearing linear and branched fluorous tags

Practical syntheses of new triarylphosphines bearing both linear and branch ed fluorous tags (Rf) are reported. The phosphines have one, two, or all th ree aryl rings bearing fluorous tags: (Ph)(3-n)P(C6H4(CH2)(m)Rf)(n) Fluorou s-organic partition coefficients have been measured and the retention prope rties of both the phosphines and the derived phosphine oxides on fluorous r everse phase silica have been studied. While applications relying on liquid -liquid extractive separations of these phosphines may be limited to those bearing three fluorous chains, the technique of solid phase extraction shou ld be broadly applicable to phosphines, phosphine oxides, and derived metal complexes. A parallel platinum-catalyzed allylation of aldehydes with fluo rous allyl stannanes illustrates the usefulness of the new fluorous ligands in small-scale synthesis.