Molecular and ionic complexes of pyrrolidinofullerene bearing chelating 3-pyridyl units

Abstract

Molecular and ionic complexes of cis-2′,5′-di(pyridin-3-yl)pyrrolidino[3′,4′:1,9](C₆₀-I_h)[5,6]fullerene DP3FP with chlorobenzene (C₆H₅Cl), manganese(II) tetraphenylporphyrin (Mn^IITPP) and tetrakis(dimethylamino)ethylene (TDAE) have been obtained for the first time. X-ray single crystal structure determination for the crystalline DP3FP·C₆H₅Cl (1) solvate proved unambiguously its molecular structure with the cis-arrangement of chelating 3-pyridyl groups. It has been demonstrated that DP3FP easily forms self-assembled photoactive complexes with metallated porphyrins. For example, the formation of a 1 : 1 complex between DP3FP and zinc (II) tetraphenylporphyrin (Zn^IITPP) in cyclohexane solution (2) was evidenced using absorption spectroscopy. A successful X-ray single crystal structure determination was performed for a self-assembled triad composed of a DP3FP molecule linked with two Mn^IITPP molecules in {DP3FP·(Mn^IITPP)₂}·(C₆H₄Cl₂)₃ (3). A strong organic donor TDAE reduces DP3FP to the radical anion state thus forming an ionic complex (TDAE˙⁺)·(DP3FP˙⁻)·(C₆H₄Cl₂)_1.6 (4). Optical, electronic and magnetic properties of 4 were investigated in detail. The performed studies strongly suggest that pyrrolidinofullerene DP3FP can be used as a building block in the design of various organic materials with advanced optoelectronic and/or magnetic properties.