Synthesis and characterization of Sn(ii) complexes supported by amino bis-phenoxide ligands

Abstract

The coordination behavior of a series of [Sn(OR)₂] systems modified by substituted amine-bis(phenolate)ligands was investigated. The complexes were synthesised from the reaction of Sn[N(SiMe₃)₂]₂ and the appropriate pro-ligand: N,N-bis(3,5-dimethyl-2-hydroxybenzyl)ethylamine (L¹H₂), N′,N‘-bis(2-hydroxy-3,5-dimethylbenzyl)-N,N-dimethylethylenediamine (L²H₂), N,N‘-bis(3,5-dimethyl-2-hydroxyphenylmethyl)-N,N‘-dimethylethylenediamine (L³H₂), 1,4-bis(2-hydroxy-3,5-dimethylbenzyl)-1,4-diazepane (L⁴H₂), 2,2′,4,4′-tetramethyl-6,6′-piperazine-1,4-diylbis(methylene)-bisphenol (L⁵H₂) and N′,N′,N′′,N′′-tetrakis(2-hydroxy-3,5-dimethylbenzyl)-1,2-ethanediamine, and the products were identified as follows: [{L¹}Sn]₂ (1), [{L²}Sn] (2), [{L³}Sn] (3), [{L⁴}Sn], (4) and [{L⁶}Sn₂]·(Py)₂ (5). Reaction of complex (1) with O₂ results in the formation of the Sn(IV) species [{L¹}₂Sn] (6), the molecular structure of which was also determined.