Silicon, phthalocyanine ligands

A series of axially-disubstituted silicon-phthalocyanines 353 (silicon-Pcs, Figure 23) was obtained by the nucleophilic displacement of one or two chlorine leaving groups from either PhSi(Pc)Cl or Si(Pc)Cl2, respectively, by reaction with the acid or alkoxide derivative of the ligand. Structure of these compounds was confirmed by H and 13C NMR, UV-vis absorption and emission spectra, electrospray or MALDI-ToF mass spectrometry as well as X-ray crystallography <2006T9433>. 

This silicon phthalocyanine with two axial ligands on silicon, a hydroxy group, and a dimethylamino-propyl siloxy group, recently entered Phase 1 dose escalation clinical studies with cutaneous lesions. No information is available as of this writing. 

Figure 7 Synthesis of a silicon(IV) phthalocyanine with defined polar axial ligands.65 Pc = phthalocyanine nucleus the centrally coordinated atom (here Si) immediately precedes the Pc acronym.

Tetracyclic tetradentate ligands (porphyrins, phthalocyanines and the like) change considerably the direction of the valent bonds of the central silicon atom transforming it into the hexa-coordinate form 3oo-304)... 

A dye molecule that has found widespread attention in the synthetic metals community is phthalocyanine 186, which can be readily made from ortho-dicyanobenzene 187 in a metal-assisted cyclotetramerization that directly provides metal complex derivatives 188 (see scheme 44) [251]. A tuning of the electronic properties is possible via the central atom and, for example, by proceeding to the related tetranaphthalene compound 189 [252]. The importance of phthalocyanines 188 in both fundamental and industrial research comes from the great number of possible applications [253]. Also, 188 can be stacked into columnar arrays by using axial ligands at the metals or by linking silicon centers as central atoms by suitable spacers [254]. The introduction of long chain alkoxy... 

Cartoni et al. [88] studied perspective of the use as stationary phases of n-nonyl- -diketonates of metals such as beryllium (m.p. 53°C), aluminium (m.p. 40°C), nickel (m.p. 48°C) and zinc (liquid at room temperature). These stationary phases show selective retention of alcohols. The retention increases from tertiary to primary alcohols. Alcohols are retained strongly on the beryllium and zinc chelates, but the greatest retention occurs on the nickel chelate. The high retention is due to the fact that the alcohols produce complexes with jS-diketonates of the above metals. Similar results were obtained with the use of di-2-ethylhexyl phosphates with zirconium, cobalt and thorium as stationary phases [89]. 6i et al. [153] used optically active copper(II) complexes as stationary phases for the separation of a-hydroxycarboxylic acid ester enantiomers. Schurig and Weber [158] used manganese(ll)—bis (3-heptafiuorobutyryl-li -camphorate) as a selective stationary phase for the resolution of racemic cycUc ethers by complexation GC. Picker and Sievers [157] proposed lanthanide metal chelates as selective complexing sorbents for GC. Suspensions of complexes in the liquid phase can also be used as stationary phases. Pecsok and Vary [90], for example, showed that suspensions of metal phthalocyanines (e.g., of iron) in a silicone fluid are able to react with volatile ligands. They were used for the separation of hexane-cyclohexane-pentanone and pentane-water-methanol mixtures. 

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