BIFUNCTIONAL CARRIERS OF ALKALI-METAL ENOLATES - THE USE OF ZIRCONIUMMESO-OCTAETHYLPORPHYRINOGEN IN ALDOL CONDENSATION-REACTIONS

The (meso-octaethylporphyrinogenato)zirconium(IV) species [(Et(8)N(4)) Zr(thf)] (1) binds the acetophenone potassium enolate [PhCOCH(2)K] (2) in its ion-pair form, 1):eta(1):eta(1)-Et(8)N(4))Zr{PhC(CH2)O}K(thf)( 3)] (3), and thus drives the aldol condensation reaction with acetophe none. The resulting aldolate, which occurs in a metallacyclic form due to the solvation of potassium by a phenyl ring, remains eta(1) (O)-bo nded to zirconium, (1):eta(1)-Et(8)N(4))Zr{PhC(CH2)OC(O)C(Me)Ph}K](n) (4).