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A new flexible hexakis-fullerene adduct with two bis(pyridin-4-ylmethyl)malonate groups located at trans-1 positions was synthesized. Via reaction with Ag(PF6) under two different conditions, two new 1D coordination polymers were obtained; under a nitrogen atmosphere, the silver ions are connected by argentophilic interactions but under an ambient atmosphere, the silver ions exhibit no interaction between them but coordination to the (H2PO4)− ions. [ABSTRACT FROM AUTHOR]

The reaction of the tetrakis[di(ethoxycarbonyl)methano]-C60 (1) with Ru3(CO)12 afforded the first bis-parallel C60–metal cluster complex: parallel-[Ru3(CO)9]2{μ3-η2,η2,η2-C60[C(COOC2H5)2]4}. The two triruthenium groups are found in either a parallel or a tilted orientation relative to each other, as determined by NMR. Only the parallel form was characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

A method for the selective synthesis of sulfide clusterfullerenes Dy 2 S@C 2 n is developed. Addition of methane to the reactive atmosphere reduces the formation of empty fullerenes in the arc-discharge synthesis, whereas the use of Dy 2 S 3 as a source of metal and sulfur affords sulfide clusterfullerenes as the main fullerene products along with smaller amounts of carbide clusterfullerenes. Two isomers of Dy 2 S@C 82 with C s (6) and C 3v (8) cage symmetry, Dy 2 S@C 72 - C s (10528), and a carbide clusterfullerene Dy 2 C 2 @C 82 - C s (6) were isolated. The molecular structure of both Dy 2 S@C 82 isomers was elucidated by single-crystal X-ray diffraction. SQUID magnetometry demonstrates that all of these clusterfullerenes exhibit hysteresis of magnetization, with Dy 2 S@C 82 - C 3v (8) being the strongest single molecule magnet in the series. DC- and AC-susceptibility measurements were used to determine magnetization relaxation times in the temperature range from 1.6 K to 70 K. Unprecedented magnetization relaxation dynamics with three consequent Orbach processes and energy barriers of 10.5, 48, and 1232 K are determined for Dy 2 S@C 82 - C 3v (8). Dy 2 S@C 82 - C s (6) exhibits faster relaxation of magnetization with two barriers of 15.2 and 523 K. Ab initio calculations were used to interpret experimental data and compare the Dy-sulfide clusterfullerenes to other Dy-clusterfullerenes. The smallest and largest barriers are ascribed to the exchange/dipolar barrier and relaxation via crystal-field states, respectively, whereas an intermediate energy barrier of 48 K in Dy 2 S@C 82 - C 3v (8) is assigned to the local phonon mode, corresponding to the librational motion of the Dy 2 S cluster inside the carbon cage.

Reaction of PPh(2)(o-C(6)H(4))(CH(2)NMeCH)C(60) (1) and (μ-H)(3)Re(3)(CO)(11)(NCMe) in refluxing chlorobenzene affords the monorhenium complex HRe(CO)(3)(η(3)-PPh(2)(o-C(6)H(4))(CH(2)NMeCH)C(60)) (2), and the dirhenium complexes (μ-H)Re(2)(CO)(7)(μ,η(3)-PPh(o-C(6)H(4))(2)(CH(2)NMeCH)C(60)) (3) and (μ-H)Re(2)(CO)(5)(μ-SSOH)(μ,η(5)-PPh(2)(o-C(6)H(4))(CH(2)NMeCH)C(60)) (4). The structures of 2-4 have been determined by an X-ray diffraction study. The oxatrisulfanyl (-SSOH) ligand of 4 likely arises from decomposition of CS(2) on silica gel during the purification processes.

Following the method of Prato et al., reaction of C(60), N-methylglycine and o-(diphenylphosphino)benzaldehyde affords PPh(2)(o-C(6)H(4))(CH(2)NMeCH)C(60) (1) in moderate yield. Compound 1 reacts with W(CO)(4)(NCMe)(2) to produce W(CO)(4)(η(3)-PPh(2)(o-C(6)H(4))(CH(2)NMeCH)C(60)) (2), through coordination of the phosphine group and one 6 : 6-ring junction of fullerene. Reaction of 1 and Os(3)(CO)(11)(NCMe) affords Os(3)(CO)(11)(PPh(2)(o-C(6)H(4))(CH(2)NMeCH)C(60)) (3), which undergoes a cluster fragmentation reaction in refluxing toluene to produce Os(CO)(3)(η(3)-PPh(2)(o-C(6)H(4))(CH(2)NMeCH)C(60)) (4). Thermal reaction of 1 and Os(3)(CO)(12) affords 3 and 4. On the other hand, reaction of 1 and Ru(3)(CO)(12) yields only the mononuclear complex Ru(CO)(3)(η(3)-PPh(2)(o-C(6)H(4))(CH(2)NMeCH)C(60)) (5). The structures of 1-3 and 5 were determined by an X-ray diffraction study.