Organolanthanide - and -pyrrolyl half-sandwich compounds: synthesis, structures, and magnetic properties

• Published in: New journal of chemistry 2023-08, Vol.47 (33), p.1565-15657
• Main Authors: She, Yeye, Lu, Yanhua, Jia, Chaohong, Li, Yahong, Zhang, Yi-Quan, Yao, Jin-lei
• Format: Article
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d3nj02225k

The utilization of the di-pyrrolyl Schiff base ligand H 2 L (H 2 L = N -((1 H -pyrrol-2-yl)methyl)-1-(1 H -pyrrol-2-yl)methanimine) in organolanthanide chemistry is presented. The 1 : 2 reaction of [Ln(N(SiMe 3 ) 2 ) 3 ] (Ln = Dy, Ho, Er, and Gd) with H 2 L in THF followed by recrystallization in THF/Tol or Tol generated complexes [Dy 2 (HL) 2 (L) 2 (THF) 2 ]·2THF ( 1 ·2THF), [Ho 2 (HL) 2 (L) 2 (THF) 2 ] ( 2 ), [Er 2 (HL) 2 (L) 2 (THF) 2 ]·4Tol ( 3 ·4Tol), and [Gd 2 (HL) 2 (L) 2 (THF) 2 ] ( 4 ). In the doubly deprotonated ligand [L] 2− , one pyrrolyl ring adopts the η 5 coordination mode, and the other pyrrolyl moiety behaves as an η 1 ligand. The deprotonated pyrrolyl scaffold of the [HL] − ligand exhibits the η 1 coordination mode. Thus, the two metal centers both display a half-sandwich configuration. Studies of the dc magnetic susceptibility of 1-4 at variable temperatures showed that weak antiferromagnetic interactions exist in these compounds. The ac magnetic susceptibility measurements for 1 and 2 indicated that they did not display single-molecule magnetic (SMM) properties. The magnetic properties of 1 and 2 were further explained by DFT calculations. Four dinuclear organolanthanide complexes were synthesized and characterized. Antiferromagnetic interactions were determined for these complexes and the magnetic properties were further explained by DFT calculations.