The preparation of new Pc-SWCNT hybrid materials is described. The synthesis of both Pd(II)Pc-SWCNT 7 and Ru(II)bis(pyridine)Pc-SWCNT 9 was carried out by esterification reaction between modified SWCNTs and the corresponding unsymmetric Pcs 1 and 2, both endowed with three solubilizing tert-butyl groups and a hydroxymethyl function. Compound 1 was prepared following the straightforward, statistical conden- sation of the corresponding phthalonitriles. However the preparation of Ru(II)bis(pyridine)Pc 2 required a multistep procedure relying on consecutive cyclotetramerization, protection, metallation and deprotection reactions. Modified SWCNT 6 was prepared, as previously described, by the Prato reaction between HiPCo nanotubes, N-methylglycine and 4-formylbenzoic acid. The COOH-containing material 6 was successfully reacted with Pd(II)Pc 1 to give Pd(II)Pc-SWCNT 7, which was fully characterized by different techniques. However, the incorporation of Ru(II)bis( pyridine)Pc 1 did not take place when applying the above-mentioned conditions. The preparation of SWCNT 8 endowed with 4-carboxyphenyl moieties was found to be essen- tial to covalently link Ru(bis(pyridine))Pc 1 to the nanotube material by ester bond formation. Although spectroscopic characterization supports the covalent binding of Pc molecules to the modified SWCNT side- walls, direct evidence of the presence of Ru(II) in the hybrid material could not be obtained.
Linking Pd(II) and Ru(II) phthalocyanines to single-walled carbon nanotubes
D'ALESSANDRO, Nicola;
2014-01-01
Abstract
The preparation of new Pc-SWCNT hybrid materials is described. The synthesis of both Pd(II)Pc-SWCNT 7 and Ru(II)bis(pyridine)Pc-SWCNT 9 was carried out by esterification reaction between modified SWCNTs and the corresponding unsymmetric Pcs 1 and 2, both endowed with three solubilizing tert-butyl groups and a hydroxymethyl function. Compound 1 was prepared following the straightforward, statistical conden- sation of the corresponding phthalonitriles. However the preparation of Ru(II)bis(pyridine)Pc 2 required a multistep procedure relying on consecutive cyclotetramerization, protection, metallation and deprotection reactions. Modified SWCNT 6 was prepared, as previously described, by the Prato reaction between HiPCo nanotubes, N-methylglycine and 4-formylbenzoic acid. The COOH-containing material 6 was successfully reacted with Pd(II)Pc 1 to give Pd(II)Pc-SWCNT 7, which was fully characterized by different techniques. However, the incorporation of Ru(II)bis( pyridine)Pc 1 did not take place when applying the above-mentioned conditions. The preparation of SWCNT 8 endowed with 4-carboxyphenyl moieties was found to be essen- tial to covalently link Ru(bis(pyridine))Pc 1 to the nanotube material by ester bond formation. Although spectroscopic characterization supports the covalent binding of Pc molecules to the modified SWCNT side- walls, direct evidence of the presence of Ru(II) in the hybrid material could not be obtained.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
