A New Type of Dendritic [60]Fullerene–Metallo‐tetraphenylporphyrin Diads (M = Zn, Co)

The synthesis of unsymmetrical malonates 19 – 23 terminated by a metallo‐tetraphenylporphyrin (M = Zn II , Co II , Co III ) and by Newkome‐type amide dendrons of generation two and three is reported. Cyclopropanation of C 60 with the second‐generation dendrons 20 and 21 leads to the formation of fullerene monoadducts 24 and 25 , representing a new type of dendritic diads. The establishment of Co in the oxidation sates of +II and +III was achieved by the treatment with Na 2 S 2 O 4 or with O 2 in the presence of CN – and SCN – , respectively, leading to the paramagnetic complex 26 and the diamagnetic axially coordinated complexes 27 . Deprotection of the tert ‐butyl groups terminating the dendritic branch of the diads 24 and 25 generates the corresponding water‐soluble systems 28 and 29 . Due to their amphiphilic character micellar aggregates are formed in water. DOSY NMR measurements showed that the aggregates consisting of 28 have an average diameter of approximately 7 nm in a buffered D 2 O solution (pH = 7.2). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)