β ‐Cyclodextrin‐Mediated Regioselective Hydrolysis of 5,10,15,20‐tetrakis[2,4‐bis(pivaloyloxy)phenyl]‐21H,23H ‐porphine

The four peripheral ester moieties of the title compound 5 are regioselectively hydrolyzed under mild conditions in the presence of β ‐cyclodextrin ( 10 ), providing a new entry to tetraphenylporphyrin derivatives with differently substituted Ph groups in the meso ‐positions. UV, 1 H‐NMR and mass spectroscopy of the inclusion complex 9 of 2,6‐ O ‐dimethyl‐β‐cyclodextrin ( 12 ) and 5 indicate a stoichiometry of 2:1 for 10/5 . Moreover, calculations confirm NOE experiments consistent with the fact that the cyclodextrins 10 and 12 approach the Ph groups of the porphyrin with the small opening of the cavity (primary face).