Octakis phthalocyanines

A novel tetraazaporphyrinato (TAP) and phthalocyaninato mixed het-eroleptic rare-earth compound, LnPc (TAP) with photochromic and electrochromic features has been readily synthesized by a one-pot reaction using Eu(acac)3-wH20, metal-free phthalocyanine H2Pc (Pc = 2,3,9,10,16,17,23,24-octakis(decyloxy)phthalo-... 

Ozkaya AR, Gurek AG, Gul A, Bekaroglu O (1997) Electrochemical and spectral properties of octakis(hexyl thio)-substituted phthalocyanines. Polyhedron 16(11) 1877—1883... 

In order to functionalize the dithienylethene backbone, we designed and synthesized successfully phthalocyanines and their analog-based dithienylethenes containing octakis (4-phenyl-buta-l,3-dienyl) substituents (TAP) and eight ferrocene units (TPF) [41,42], as shown in Scheme 13 and Scheme 14. 

Recently, Swager has compared the mesomorphic properties of an octakis(tetra-decyloxymethyl)-phthalocyanine coppeifll) complex, Crys 80-Colhd 280-I, with the analogous octakis(tetradecyloxymethyl)tetra-2,3-thiophenoporphyiazine, Crys 49-Colhd 258-I [134]. X-ray difiiaction studies show that the lattice constants are 33.5 A for the phthalocyanine complex and 32.9 A for the thiophenoporphyr-... 

A cholesteric phase represents a special case of a nematic phase. The planes of adjacent molecules are also parallel, but the longitudinal axis of adjacent planes are turned about a definite angle. The result is a screw structure of the system. Cholesteric thermotropic liquid crystalline phthalocyanines are also known. ( + )-2,3,9,10,16,17,23,24-octakis[4-(dodecyloxy)-2-oxapentyl]phthalo-cyanine (preparation see Schemes 13 and 14) shows a texture typical for cholesteric phases [155], At 160°C, this compound gives a fluid isotropic phase. Upon cooling an anisotropic phase appears at 153 °C. The texture similar to platelets (blue phase) changes at 66 °C to typical cholesteric fan-shape structure and remains fan-shaped down to room temperature. Except for the discotic... 

Apart from the triphenylene mentioned in Section 11.2, one other case has been reported where a chiral columnar phase structure manifests itself in an asymmetric texture 2,3,9,10,16,17,23,24-octakis-(5-3,7-dimethyloctyloxy)-phthalocyanine exhibits two columnar phases above room temperature [8], [14]. The one at the higher temperature has a rectangular column lattice, the other a hexagonal one. When cooled quickly from the isotropic liquid, left-handed spirals appear in the flower-like texture of the highly ordered room temperature phase (Figure 11.8). X-ray and circular dichroism measurements indicate a helical superstructure with a pitch of 55 A (a 16 molecules). It seems very probable that in this case the molecules are weakly tilted and that the tilt direction spirals around the column axis, especially because the phase at higher temperatures is rectangular and therefore most probably tilted as well. 

Di(trifluoroethoxy)phthalodinitrile 122 can be prepared from 2,3-dicyanohydroquinone 121 by alkylation with trifluoroethyltosylate in DMF [70], The 4,5-substituted dinitrile 125 is available from the 4,5-dibromocatechol 123 by consecutive alkylation with tosylate (DMF, K2CO3) and cyanation (CuCN, DMF) [70], 0=Ti" complexes of a- and p-octakis(trifluoroethoxy)phthalocyanines were prepared using these dinitriles 122 and 125 [70]. The Zn" complex of p-octasubstituted phthalocyanine was also reported [78],... 

Chen MJ, Fremgen DE, Rathke JW (1998) Oxygen atom transfer from p-oxo-bis[l,4,8,11,15,18,22,25-octakis(trifluoromethyl)phthalocyanmato]diiron(lll) evidence for an Fe =0 intermediate. J Porphyrins Phthalocyanines 2 473 82... 

Mashazi P, Antunes E, Nyokong T (2010) Probing electrochemical and electrocatalytic properties of cobalt(II) and manganese(lll) octakis(hexylthio) phthalocyanine as self-assembled monolayers. J Porphyrins Phthalocyanines 14(ll) 932-947... 

Gurek AG, Basova T, Euneau D, Lebrun C, Kol tsov E, Hassan AK et al (2006) Synthesis, structure, and spectroscopic and magnetic properties of mesomorphic octakis(hexylthio)-substituted phthalocyanine rare-earth metal sandwich complexes. Inorg Chem 45(4) 1667-1676... 

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