The design and self-assembly of three supramolecular triangles is described. A novel 60 degrees corner unit directs the exclusive formation of triangular assemblies that are not in detectable equilibrium with other macrocycles. The resulting triangles have sides ranging from 2.7 to 3.5 nm in length and molecular masses as high as 5396 amu. The crystal structure of one of the assemblies shows an approximately 1.4 nm cavity; the crystal packing forms open, triangular channels. The characterization of the supramolecular triangles by multinuclear NMR, elemental analysis, and electrospray mass spectrometry is also reported.

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meso-Tetrakis(4-chlorophenyl)porphinato)manganese(III) tetracyanoethenide, [MnTClPP][TCNE], has been prepared and structurally characterized as the toluene and dichloromethane disolvates, and the magnetic and thermal properties of these solvates, as well as their corresponding desolvates, have been determined. The ditoluene solvate (1) has a triclinic unit cell: P1 h, a ) 10.171 (4) Å, b ) 10.189(3) Å, c ) 14.522 (3) Å, R ) 107.51(2)°, ) 85.58(2)°, γ ) 111.51(3)°, Z ) 1. The bis(dichloromethane) solvate (2) belongs to the monoclinic unit cell: P2 1 /n, a ) 9.894(2) Å, b ) 10.697(2) Å, c ) 23.560(5) Å, ) 101.34(2)°, Z ) 2. The cation is typical with average Mn-N distances of 2.012 Å for both the toluene and dichloromethane solvates. The bonding distances for both planar anions are characteristic of [TCNE] •-. Both solvates have an uniform linear chain (1-D) coordination-polymer structure comprised of alternating cations and anions. Each [TCNE] •-binds to two Mn III 's in a trans-µ-N-σ-bound manner with Mn-N spacings of 2.267 (1) and 2.276 Å (2). The Mn-N-C angles are 167.2 and 143.1°, while intrachain Mn‚‚‚Mn separations are 10.189 and 9.894 Å, and the dihedral angle between the MnN 4 and [TCNE] •-mean planes are 86.8 and 52.4°for 1 and 2, respectively. The ν CN absorptions for the toluene and dichloromethane solvates occur at 2201 m and 2160 s cm -1 and 2195 m and 2138 s cm -1 , respectively. Upon thermolysis at 175°C 1 desolvates to R-[MnTClPP][TCNE] with ν CN absorptions at 2201 m and 2159 s cm -1 . In contrast, desolvation of 1 in refluxing n-octane leads to -[MnTclPP][TCNE] with ν CN absorptions at 2190 m and 2132 s cm -1 . Upon facile desolvation of 2 to form γ-[MnTClPP][TCNE] the nitrile absorptions remain essentially unchanged (2195 m and 2137 s cm -1 ). For 1 and R the susceptibilities can be fit by the Curie-Weiss expression with Θ ) -60 K (T > 210 K) and -10 K (T > 250 K) and an effective Θ, Θ′ of +13 (50 < T < 120 K) and 29 K (60 < T < 160 K), respectively. Θ is not observed for the 2 or the -or γ-phase; however, Θ′ for the 2 and the -and γ-phases are 58, 92, and 86 K, respectively. The magnetic data are consistent with linear chain ferrimagnets comprised of antiferromagnetically coupled S ) 2 Mn III sites and S ) 1 / 2 [TCNE] •-sites with the antiferromagnetic intrachain coupling, J/k B (k B ) Boltzmann's constant) determined from fits to the Seiden expression, of -33, -160, -65, -267, and -265 K for the 1, 2, and R-, -, and γ-phases, respectively. Hysteresis with a coercive field of 5.8 kOe is observed for 1 at 2 K. Metamagnetic behavior below 5 K is observed for the 1, 2, and -and γ-phases with critical fields of 10, 27, 27, and 27 kOe, respectively. The ordering temperatures, T c , determined from the maxima in the ′(T) data taken at 10 Hz, are 8.8, 6.7, 11.1, 14.1, and 11.4 K for the phases 1, R, , 2, and γ, respectively. Desolvation of 1 and 2 increases the magnetic disorder and the magnetic coupling.

We report that an equilibrium mixture of triangular and square supramolecular species results when the flexible, ditopic donor unit, trans-bis(4-pyridyl)ethylene, is reacted with the ditopic acceptor unit, cis-(Me(3)P)(2)Pt(OTf)(2), in a one-to-one ratio. Both products are characterized in solution, by way of multinuclear NMR, and in the solid state, via X-ray crystallography. The effects of water and anions, cobalticarborane versus triflate, on the equilibrium are probed. The selective crystallization of either of the two species can be accomplished via the appropriate choice of solvents and ratio of anions present in the system. The dominant species in solution is not always consistent with the most prevalent species in the solid state.

A series of neutral, platinum-based macrocycles was synthesized from rigid oxygen donor building blocks via self-assembly. The combination of a platinum-based 60 degrees acceptor unit 1 with several linear and angular dicarboxylate bridging ligands afforded hitherto unknown neutral platinum-based supramolecular triangles and rhomboids. In addition, a similar reaction of the diplatinum molecular clip 6 and three different linear dicarboxylates led to the formation of neutral molecular rectangles. Most of the macrocycles were characterized by X-ray single-crystal structure analysis, and, in all cases, NMR spectra were consistent with the formation of single highly symmetrical species.