Synthesis, Crystal Structures, and Properties of Oxovanadium(IV)–Lanthanide(III) Heteronuclear Complexes

✍ Scribed by Wei Shi; Xiao-Yan Chen; Yan-Nan Zhao; Bin Zhao; Peng Cheng; Ao Yu; Hai-Bin Song; Hong-Gen Wang; Dai-Zheng Liao; Shi-Ping Yan; Zong-Hui Jiang

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 220 KB
• Volume: 11
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.200500086

✦ Synopsis

Abstract

A new series of oxovanadium(IV)–lanthanide(III) heteronuclear complexes [Yb(H~2~O)~8~]~2~[(VO)~2~(TTHA)]~3~⋅21 H~2~O (1), {[Ho(H~2~O)~7~(VO)~2~(TTHA)][(VO)~2~(TTHA)]~0.5~}⋅ 8.5 H~2~O (2), {[Gd(H~2~O)~7~(VO)~2~(TTHA)][(VO)~2~(TTHA)]~0.5~}⋅8.5 H~2~O (3), {[Eu(H~2~O)~7~][(VO)~2~(TTHA)]~1.5~}⋅ 10.5 H~2~O (4), and [Pr~2~(H~2~O)~6~(SO~4~)~2~][(VO)~2~(TTHA)] (5) (H~6~TTHA=triethylenetetraaminehexaacetic acid) were prepared by using the bulky flexible organic acid H~6~TTHA as structure‐directing agent. X‐ray crystallographic studies reveal that they contain the same [(VO)~2~(TTHA)]^2−^ unit as building block, but the Ln^3+^ ion lies in different coordination environments. Although the lanthanide ions always exhibit similar chemical behavior, the structures of the complexes are not homologous. Compound 1 is composed of a [Yb(H~2~O)~8~]^3+^ ion and a [(VO)~2~(TTHA)]^2−^ ion. Compounds 2 and 3 are isomorphous; both contain a trinuclear [Ln(H~2~O)~7~(VO)~2~(TTHA)]^+^ (Ln=Ho for 2 and Gd for 3) ion and a [(VO)~2~(TTHA)]^2−^ ion. Compound 4 is an extended one‐dimensional chain, in which each Eu^3+^ ion links two [(VO)~2~(TTHA)]^2−^ ions. For 5, the structure is further assembled into a three‐dimensional network with an interesting framework topology comprising V~2~Pr~2~ and V~4~Pr~2~ heterometallic lattices. Moreover, 4 and 5 are the first oxovanadium(IV)–lanthanide(III) coordination polymers and thus enlarge the realm of 3d–4f complexes. The IR, UV/Vis, and EPR spectra and the magnetic properties of the heterometallic complexes were studied. Notably, 2 shows unusual ferromagnetic interactions between the VO^2+^ and Ho^3+^ ions.