FULL PAPER DOI: 10.1002/ejic.200800192 Reactivity of Cationic Lanthanide(III) Monoporphyrinates towards Anionic Cyanometallates – Preparation, Crystal Structure, and Luminescence Properties of Cyanido-Bridged Di- and Trinuclear d–f Complexes Xunjin Zhu, [a] Wai-Kwok Wong,* [a] Jianping Guo, [b] Wai-Yeung Wong, [a] and Jie-Peng Zhang [c] Keywords: Lanthanides / Porphyrins / Cyanometallates / Cyanido-bridged d–f complexes / Near-infrared emission The metathesis reaction between two equivalents of [Ln- (tpp)(H 2 O) 3 ]Cl (Ln = Yb, Er; tpp 2– = tetraphenylporphyrinate dianion) and one equivalent of cyanometallate in dmf at room temperature under nitrogen for 24 hours gave the cyan- ido-bridged d–f trinuclear complexes [{Ln(tpp)(dmf) n } 2 {(μ- NC) 2 M(CN) 2 }] (Ln = Yb, n = 2, M = Ni, 1; Ln = Er, n = 3, M = Ni, 2; Ln = Yb, n = 2, M = Pt, 3; Ln = Er, n = 3, M = Pt, 4), a trinuclear complex [{Er(tpp)(dmf) 2 }{(μ-NC) 2 Fe(CN) 4 }{Er- (Htpp)(dmf) 2 }] (5), and a dinuclear complex [{Er(tpp)(dmf)- (H 2 O)}(μ-NC)Ag(CN)] (6) when the cyanometallate used was the dianion [M(CN) 4 ] 2– (M = Ni, Pt), the trianion [Fe- (CN) 6 ] 3– , and monoanion [Ag(CN) 2 ] – , respectively. The solid- Introduction Porphyrinatolanthanide complexes are continuing to at- tract considerable research interest, not only for their po- tential biological and chemical importance, but also for the opportunity they offer to study structure–bonding–reactiv- ity interrelationships. [1–3] Therefore, much effort has been devoted to the synthesis of novel complexes and investiga- tion of their unique properties. Previously, we reported a convenient method for the preparation of cationic mono- porphyrinatolanthanide complexes, [Ln(por)(H 2 O) 3 ]Cl (por = porphyrinate dianion), by the reaction of Ln[N(Si- Me 3 ) 2 ] 3 ·x[LiCl(thf) 3 ] with porphyrin free base (H 2 por) in bis(methoxyethyl) ether. [4,5] X-ray diffraction studies showed that the lanthanide ions are seven-coordinate, sur- rounded by four N atoms of the porphyrin ring and three O atoms of the aqua ligands. Due to the lability of aqua molecules, these complexes catalyze the cyclotrimerization [a] Department of Chemistry and Centre for Advanced Lumines- cence Materials, Hong Kong Baptist University, Kowloon Tong, Hong Kong, P. R. China E-mail: wkwong@hkbu.edu.hk Fax: +852-3411-5862 [b] Department of Chemistry, Shanxi Universtiy, Taiyuan, Shanxi, P. R. China [c] School of Chemistry & Chemical Engineering, Sun Yat-Sen University, Guangzhou, 510275, P. R. China Supporting information for this article is available on the WWW under http://www.eurjic.org or from the author. Eur. J. Inorg. Chem. 2008, 3515–3523 © 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 3515 state structures of these complexes were ascertained by X- ray crystallography. Photoluminescence studies of complexes 1–4 showed that these complexes displayed photophysical properties characteristic of normal metal–porphyrinato com- plexes. Their absorption bands and emission peaks in the vis- ible region are typical of the intraligand ππ* transitions of the porphyrinato ligand. Furthermore, these complexes also exhibited emission characteristic of the lanthanide(III) ion in the near-infrared (NIR) region, which was quenched by the cyanometallates. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) of phenylisocyanate efficiently [5] and can form adducts with anionic tripodal ligands such as cyclopentadienyltris(di- methylphosphito) cobaltate(I) (L OMe – ) and hydridotris(pyr- azole-1-yl)borate (T p H– ) by a displacement reaction under mild conditions. [6] Furthermore, cationic monoporphyrin- atolanthanide complexes [Yb(por)(H 2 O) 3 ]Cl have a high tendency to form different metal dimers bridged by OH – ions, chloride ions, or water molecules under different reac- tion conditions. [7] Therefore, [Ln(por)(H 2 O) 3 ]Cl is a very versatile reagent for the preparation of species containing lanthanide porphyrinate and is a good candidate for the investigation of structure–reactivity relationships. Cyanido- bridged d–f complexes exhibit very rich and interesting structural, magnetic, and photophysical properties. Their structural and magnetic properties have been studied exten- sively; [8,9] however, their photophysical properties were only explored recently. [10] We have been interested in the synthe- sis and photoluminescence properties of d–f complexes [11] and porphyrinatolanthanide(III) complexes. [12] We would like to extend our study to cyanido-bridged, heterometallic d–f porphyrinato complexes. Cyanido-bridged d–f com- plexes can be conveniently synthesized by the metathesis reaction between a lanthanide(II or III) salt and a cyano- metallate of transition metals in highly polar solvents. [8–10] The cationic lanthanide(III) complex [Ln(por)(H 2 O) 3 ]Cl would be an ideal precursor complex for the preparation of such cyanido-bridged d–f porphyrinato complexes. Here we report the characterization and photophysical properties of