Michael T. M. Choi

Double-decker yttrium(III) complexes with phthalocyaninato and porphyrinato ligands

A series of new yttrium(III) double-decker complexes with the same and different phthalocyaninato and porphyrinato ligands has been prepared. The homoleptic complexes Y(P)2 (P = Pc*(C7H15)8, Pc*(OC5H11)8; Pc* = 2,3,9,10,16,17,23,24-octasubstituted phthalocyaninate) have been synthesized by treating yttrium(III) acetylacetonate (Y(acac)3·H2O) with the phthalonitriles C6H2R2(CN)2 (R = C7H15, OC5H11) in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). The heteroleptic analogues Y(P)(Pc) (P = Pc*(C7H15)8, Pc*(OC5H11)8; Pc = unsubstituted phthalocyaninate) and Y(P)(Por) (P = Pc, Pc*(C7H15)8; Por = meso-tetraphenylporphyrinate (TPP), meso-tetra(4-pyridyl)porphyrinate (TPyP)) have been prepared by the base-catalysed tetramerization of the corresponding phthalonitriles using Y(P)(acac) (P = Pc, TPP, TPyP) as templates. The syntheses along with the spectroscopic and electrochemical properties of these novel double-deckers are described.

A new pathway to heteroleptic double-decker (phthalocyaninato)(porphyrinato)europium(III) complexes

Abstract Treatment of europium(III) acetylacetonate [Eu(acac)3 · nH2O] with metal-free porphyrins 5,10,15,20-tetraphenylporphyrin [H2(TPP)], 5,10,15,20-tetra(4-pyridyl)porphyrin [H2(TPyP)], 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin [H2(TMPP)], 5,10,15,20-tetrakis(4-chlorophenyl)porphyrin [H2(TCPP)] or 5,10,15,20-tetrakis(4-tert-butylphenyl)porphyrin [H2(TBPP)] gave the half-sandwich complexes Eu(Por)(acac) (Por=TPP, TPyP, TMPP, TCPP, TBPP), which reacted with phthalonitriles C6H2R2(CN)2 (R=H, C7H15, OC5H11) in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to give the respective heteroleptic double-decker complexes Eu[Pc∗(R)8](Por) (Pc∗=2,3,9,10,16,17,23,24-octasubstituted phthalocyaninate; R=H, C7H15, OC5H11) in moderate yields. All of the mixed sandwich compounds were characterized with spectroscopic methods including UV-vis, near IR, IR and mass spectrometry.

New dimeric supramolecular structure of mixed (phthalocyaninato)(porphyrinato)europium(III) sandwiches: preparation and spectroscopic characteristics

The mixed double-decker Eu[Pc(15C5)4](TPP) (1) was obtained by base-catalysed tetramerisation of 4,5-dicyanobenzo-15-crown-5 using the half-sandwich complex Eu(TPP)(acac) (acac = acetylacetonate), generated in situ, as the template. For comparative studies, the mixed triple-decker complexes Eu2[Pc(15C5)4](TPP)2 (2) and Eu2[Pc(15C5)4]2(TPP) (3) were also synthesised by the raise-by-one-story method. These mixed ring sandwich complexes were characterised by various spectroscopic methods. Up to four one-electron oxidations and two one-electron reductions were revealed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). As shown by electronic absorption and infrared spectroscopy, supramolecular dimers (SM1 and SM3) were formed from the corresponding double-decker 1 and triple-decker 3 in the presence of potassium ions in MeOH/CHCl3.

Synthesis and molecular structure of a head-to-tail [4+4] dimer of a hexa-substituted anthracene

Two hexa-substituted anthracenes have been synthesised; the molecular structure of a [4+4] head-to-tail anthracene dimer has also been determined by X-ray diffraction analysis.