The synthesis of novel magnesium, copper, and metal-free porphyrazines, peripherally substituted with dithia-7-crown-2 (MPz(7)), dithia-15-crown-5 (MPz(15)), and dithia-18-crown-6 (MPz(18)) macrocycles is reported. These compounds are prepared starting from dicyanoethylene containing crown ethers 3, 2(1), and 2(2), respectively, which contain sulfur as well as oxygen heteroatoms. The "crowned" porphyrazines bind silver(I) and mercury-(II) perchlorates. UV/vis spectroscopy and electron paramagnetic resonance measurements reveal that addition of the transition-metal ions leads to dimerization of the porphyrazine complexes. In the case of the dithia-18-crown-6-substituted porphyrazines, the dimers break up to form monomeric 6:1 guest-host complexes when more than 2 equiv of the metal ion is added. The single-crystal structures of the crown ether 2(2) and the porphyrazine MgPz (18) . The structure refinement converged to R 1 = 0.0839 and wR2 = 0.2196. The electrical properties of H2PZO8) have been studied by complex impedance spectroscopy. The bulk electrical conductivity of this compound is approximately 1 order of magnitude higher than that of the corresponding 18-crown-6 phthalocyanine. roduction olecular ionics is a rapidly developing area in chemistry, aimed at the development of molecular systems and devices t can handle and store information using ions as the basic ties. 1-3 Crown ethers, which are capable of selectively ding alkali metal ions, are important building blocks for structing such devices because metal complexation can lead specific response, e.g. a change in electrical conductivity, rder to maximize the reliability, the response must be highly linear, which can be achieved by introducing a cooperative ct in the binding process.2*3 hthalocyanines (Pcs), porphyrins (Pps), and porphyrazines ) are compounds of another class receiving great interest omponents in molecular ionics.4 Pps containing pendant n ether macrocycles were first described by Thanabal and Kobayashi.5 O f particular interest are phthalocyanines substituted with four crown ether rings,2,3 which were reported independently by the groups of Bekaroglu, Kobayashi, and Nolte.6 These compounds display solvent and metal ion induced aggregation behavior.7 We have prepared complexes of crown ether Pcs with various alkali metal picrates and studied the electrical properties of these systems.8,9 The ac electrical conductivities of the K +, Rb+, and Cs+ complexes of 18-crown-6 Pc were shown to be 2-3 orders of magnitude higher than those of the free molecules. It was demonstrated that these higher conductivities are due to the fact that in the complexes the phthalocyanines have a cofacially stacked arrangement. With Ba2+, noncofacial aggregates are formed, which show lower conductivities. The most promising application of crown ether phthalocyanines and their complexes is as sensor materials in gas sensors. 10,11 Other crowned Pcs that have been synthesized and studied are Pcs with azacrown ether and thiacrown ether substituents, Chemistry,...

Abstract. The synthesis of magnesium porphyrazines substituted with sulfur-containing 15-crown-5 and 18-crown-6 macrocycles is reported as well as the single crystal structure of the 18-crown-6 substituted porphyrazine; the larger crown ether compound is shown to form dimers with Ag+ ions, unlike the porphyrazine with the smaller crown ether rings. Supramolecular structures from phthalocyanine and porphyrin building blocks are currently receiving great interest.1-6 As part of our program aimed at the development of conducting materials7 from such structures, we describe here the first synthesis and metal ion binding properties of novel porphyrazines l(n) (n= 1,2) substituted at the P-positions with crown-ether rings. In addition, we present the first X-ray structure of a crowned porphyridphthalocyanine type of molecule. The crown ether precursors 2(1) and 2(2) were prepared from sodium cis-1,2-dicyano-1,2-ethylenedithiolate8 and tetraethyleneglycol-dichloride (1 1 % yield) and pentaethyleneglycol-dichloride (23% yield), respectively, according to a slightly modified literature pro~edure.~ To a boiling suspension of 5 mmol magnesium in 10 mL npropanol was added a solution of 1 mmol of 2(n) in 10 mL n-propanol and the reaction mixture was refluxed for 18 h. The product was isolated and purified by washing with acetone and dry diethylether and subsequently by column chromatography (NaBr impregnated silica, eluent 2% MeOH in CHC13 for 1(1), and 10% MeOH in CHC13 for l(2)). Compounds l(1) and l(2) were obtained as dark blue fb3 e, ,s powders in yields of 22% and 20%, respectively (1n.p. > 320 "C).t Single crystals of l(2) were grown from CHC13/MeOH (1:l). X-ray data were collected on an Enraf-Nonius Cad4-Ttrotating anode diffractometer [MoKa (Mon); 150 K1. The compound crystallized in a triclinic unit cell, spaceroup P1, a = 9.584(3) 8, b = 17.672(2) A, c = 19.620 (4) x, ~1 = 84.904(14)", p = 85.21(2)", y = 89.29(2)", V = 3298.3(13) A3, Z = 2. The structure was solved with SIR92 and refined using SHELXL92, resulting in R1 = 0.093, wR2 = 0.252, and S = 0.983. A PLUTON-plot is presented in Figure 1. The magnesium atom in the center of the porphyrazine is coordinated by one water molecule (probably from the solvent), which is linked with two bifurcated H-bonds to the crown ether ring of a neighboring porphyrazine. In this way a linear staircase-like structure is obtained. The nearest distance between the centers of two porphyrazine molecules amounts to 9.584(5) 8. A detailed description of the structure will be published elsewhere.1° The binding affinities of compounds l ( n ) for silver(1) perchlorate were evaluated by UV/vis spectroscopy. On addition of an AgC104 solution to a solution of the 18-crown-6 derivative l(2) in 5% MeOH in CHC13, the t The products were fully characterized by elemental analysis and spectroscopic techniques. Compound 1 (1): UV/vis (CHC13) kmax/nm(log E): 675

A series of multi‐porphyrin arrays were synthesized and the self‐assembly behaviour of these compounds at the air–water interface was investigated by the Langmuir–Blodgett technique. It was found that as the overall area of the porphyrin molecules was increased, upon going from a mono‐ to bis‐ to a tetra‐ and then to hexaporphyrin species, the intermolecular stacking between the molecules also increases, resulting in more stable monolayers. In the case of the hexaporphyrin species the intermolecular interactions are so strong that monolayer formation is irreversible. All porphyrin monolayers can be transferred to a glass surface with good transfer ratios, leading to highly ordered porphyrin films in which the chromophores are arranged orthogonal to the glass surface. Copyright © 2001 John Wiley & Sons, Ltd.