1144563-01-8Relevant articles and documents
Syntheses, X-ray structures, and redox behaviour of the group 14 bis-boraamidinates MPhB(μ-N-t-Bu)22 (M = Ge, Sn) and Li2MPhB(μ-N-t-Bu)22 (M = Sn, Pb)
Konu, Jari,Tuononen, Heikki M.,Chivers, Tristram
, p. 461 - 471 (2009)
The solid-state structures of the complexes M[PhB(μ-N-t-Bu) 2]2 (1a, M= Ge; 1b, M = Sn) were determined to spirocyclic with two orthogonal boraamidinate (bam) ligands N,N'-chelated to the group 14 centre. Oxidation of 1b with2Cl2afforded the thermally unstable, blue radical cation {Sn[PhB(m-N-t-Bu)2]2}-+, identified by electron paramagnetic (EPR) spectroscopy supported by density functional theory (DFT) calculations, whereas the germanium analogue 1a was inert towards SO 2Cl2. The reaction between Li2[PhB(μ-N-t-Bu) 2]2 and SnCl2 or PbI2 in 2:1 molar ratio in diethyl produced the novel heterotrimetallic complexes Li 2Sn[PhB(μ-N-t-Bu)2]2 (2b) and (Et2O-Li)LiPb[PhB(μ-N-t-Bu)2]2 (2c-OEt2), respectively. By contrast, treatment of Li2[PhB(μ-N-t-Bu) 2]2 with C4H8O2-GeCl2 yielded the germanium(IV) 1a via a redox process. The X-ray structures of 2b and 2c-THF revealed polycyclic arrangements in which one bam ligand is N,N'-chelated to the Sn(II) or Pb(II) atom and one of the Li+ cations, while the second bam ligand exhibits a bonding mode, bridging all three metal centres. The fluctional behaviour of 2b was investigated by variable temperature, NMR spectroscopy.