Magnetic and Structural Transitions at Dimerization of C60•− in Ionic Fullerene Complexes with Metalloporphyrins: {(TMP+)2·MIITPP}·(C60−)2·(C6H4Cl2)2·(C6H5CN)2 (M = Zn and Mn)

Negatively charged singly-bonded dimers of C1-[C70(CF3)10] and bare C70 fullerene

Singly-bonded {C₇₀(CF₃)₁₀⁻}₂ and (C₇₀⁻)₂ dimers are obtained as crystalline salts allowing their molecular structure, and optical and magnetic properties to be studied.

The molecular structure of high-spin (S = 5/2) manganese(II) phthalocyanine in tetrabutylammonium bromido(phthalocyaninato)manganese(II)

The title complex salt, (C16H36N)[MnBr(C32H16N8)] or (TBA)[Mn(II)Br(Pc)] (TBA is tetrabutylammonium and Pc is phthalocyaninate), has been obtained as single crystals by the diffusion technique and its crystal structure was determined using X-ray diffraction. The high-spin (S = 5/2) [Mn(II)Br(Pc)](-) macrocycle has a concave conformation, with an average equatorial Mn-N(Pc) bond length of 2.1187 (19) Å, an axial Mn-Br bond length of 2.5493 (7) Å and with the Mn(II) cation displaced out of the 24-atom Pc plane by 0.894 (2) Å. The geometry of the Mn(II)N4 fragment in [Mn(II)Br(Pc)](-) is similar to that of the high-spin (S = 5/2) manganese(II) tetraphenylporphyrin (TPP) in [Mn(II)(1-MeIm)(TPP)] (1-MeIm is 1-methylimidazole).

Structure and optical properties of fullerene C60 complex with dipyridinated iron(II) phthalocyanine [Fe(II)Pc(C5H5N)2]·C60·4C6H4Cl2: First structure of bisaxially coordinated iron(II) phthalocyanine complex with acetonitrile Fe(II)Pc(CH3CN)2

The complex of fullerene C 60 with dipyridinated iron(II) phthalocyanine [ Fe ( II ) Pc ( C 5 H 5 N )2]· C 60·4 C 6 H 4 Cl 2 (1) has been obtained as single crystals. According to the IR- and UV-visible-NIR spectra, 1 is molecular solid with no charge transfer from Fe ( II ) Pc ( C 5 H 5 N )2 to C 60· C 60 molecules form closely packed linear columns in 1 along the b axis with a uniform interfullerene center-to center distance of 9.99 Å and multiple short van der Waals (vdW) C … C contacts between fullerenes of 3.10–3.18 Å. Totally each Fe ( II ) Pc ( C 5 H 5 N )2 unit is surrounded by four C 60 molecules two of which form short vdW C … C contacts with the phthalocyanine plane locating near two adjacent phenylene substituents of Fe ( II ) Pc . The Fe ( II ) Pc ( C 5 H 5 N )2 geometry remains almost unchanged as compared with that of fullerene free Fe ( II ) Pc ( C 5 H 5 N )2. The iron(II) atoms are located exactly in the Pc plane, the Fe - N ( C 5 H 5 N ) bond length is 2.038(3) Å and the averaged of the Fe - N ( Pc ) bond length is 1.935(3) Å. Bisaxially coordinated iron(II) phthalocyanine complex with acetonitrile Fe ( II ) Pc ( CH 3 CN )2 does not cocrystallize with C 60. Nevertheless, good quality crystals of [ Fe ( II ) Pc ( CH 3 CN )2]·2 C 6 H 4 Cl 2 (2) were isolated in this synthesis. That is the first structure of bisaxially coordinated metal phthalocyanine complex with nitrile containing solvent. Acetonitrile unusually strongly coordinates to Fe ( II ) Pc with the Fe – N ( CH 3 CN ) bond length of 1.938(1) Å. The iron(II) atoms are located in the Pc plane and the averaged length of the Fe - N ( Pc ) bonds is 1.934(1) Å.

Design, crystal structures and magnetic properties of anionic salts containing fullerene C60 and indium(iii) bromide phthalocyanine radical anions

Salts containing fullerene C₆₀ and indium(iii) bromide phthalocyanine (Pc) radical anions, (TBA⁺)₃(C₆₀˙⁻){In^III(Br)(Pc)˙⁻}(Br⁻)·C₆H₄Cl₂ (1) and (TEA⁺)₂(C₆₀˙⁻){In^III(Br)(Pc)˙⁻}·C₆H₄Cl₂·C₆H₁₄ (2), have been obtained and their structures, optical and magnetic properties are discussed.

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

Molecular and ionic complexes of cis-2',5'-di(pyridin-3-yl)pyrrolidino[3',4':1,9](C(60)-I(h))[5,6]fullerene DP3FP with chlorobenzene (C(6)H(5)Cl), manganese(II) tetraphenylporphyrin (Mn(II)TPP) and tetrakis(dimethylamino)ethylene (TDAE) have been obtained for the first time. X-ray single crystal structure determination for the crystalline DP3FP·C(6)H(5)Cl (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(II)TPP) 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(II)TPP molecules in {DP3FP·(Mn(II)TPP)(2)}·(C(6)H(4)Cl(2))(3) (3). A strong organic donor TDAE reduces DP3FP to the radical anion state thus forming an ionic complex (TDAE˙(+))·(DP3FP˙(-))·(C(6)H(4)Cl(2))(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.

Synthesis and structure analysis of (K[DB18 C6])4(C60)5·12THF containing C60 in three different bonding states

A new fulleride, (K[DB18C6])(4)(C(60))(5)·12THF, was prepared in solution using the "break-and-seal" approach by reacting potassium, fullerene, and dibenzo[18]crown-6 in tetrahydrofuran. Single crystals were grown from solution by the modified "temperature difference method". X-ray analysis was performed revealing a reversible phase transition occurring on cooling. Three different crystal structures of the title compound at different temperatures of data acquisition are addressed in detail: the "high-temperature phase" at 225 K (C2, Z=2, a=49.055(1), b=15.075(3), c=18.312(4) Å, β=97.89(3)°), the "transitional phase" at 175 K (C2 m, Z=2, a=48.436(5), b=15.128(1), c=18.280(2) Å, β=97.90(1)°), and the "low-temperature phase" at 125 K (Cc, Z=4, a=56.239(1), b=15.112(3), c=36.425(7) Å, β=121.99(1)°). On cooling, partial radical recombination of C(60)(·-) into the (C(60))(2)(2-) dimeric dianion occurs; this is first time that the fully ordered dimer has been observed. Further cooling leads to formation of a superstructure with doubled cell volume in a different space group. Below 125 K, C(60) exists in the structure in three different bonding states: in the form of C(60)(·-) radical ions, (C(60))(2)(2-) dianions, and neutral C(60), this being without precedent in the fullerene chemistry, as well. Experimental observations of one conformation exclusively of the fullerene dimer in the crystal structure are further explained on the basis of DFT calculations considering charge distribution patterns. Temperature-dependent measurements of magnetic susceptibility at different magnetic fields confirm the phase transition occurring at about 220 K as observed crystallographically, and enable for unambiguous charge assignment to the different C(60) species in the title fulleride.