MN(III)-TETRAARYLPORPHYRINS BEARING COVALENTLY BONDED CROWN-ETHERS - SYNTHESIS AND CATALYTIC ACTIVITY IN 1-DODECENE EPOXIDATION PROMOTED BYAQUEOUS HOC1 OC1(-)/

Mn(III)-complexes of tetraarylporphyrins 1-4 bearing a crown-ether cov alently linked through a single flexible chain have been synthesized. Their basic frame is that of the robust tetra-(2,6-dichlorophenyl)porp hyrin 5 and the chain is connected by ether linkage either to the orth o (1-2) or to the meta positions (3-4) of one meso-aryl group. Catalyt ic efficiency was tested in the epoxidation of the poorly reactive 1-d odecene at 0 degrees C under CH2Cl2/H2O two-phase conditions in the pr esence of NaOCl (pH 9.5-10.0) as oxygen donor. The results obtained le d us to propose a general acid/base catalysis as an explanation for th e positive effect of crown-ethers in the alkene epoxidations with this catalytic system.