Crystallographic characterization of rare-earth cyano-tri-phenyl-borate complexes and the cyano-borates [NCBPh], [NCBPhMe], and [NCBPh(μ-O)BPh].

The investigation of the coordination chemistry of rare-earth metal complexes with cyanide ligands led to the isolation and crystallographic characterization of the cyano-tri-phenyl-borate complexes di-chlorido-(cyano-tri-phenyl-borato-κ)tetra-kis-(tetra-hydro-furan-κ)lanthanide(III), [Cl(CHBN)(CHO)] [lanthanide () = dysprosium (Dy) and yttrium Y)] from reactions of LnCl, KCN, and NaBPh. Attempts to independently synthesize the tetra-ethyl-ammonium salt of (NCBPh) from BPh and [NEt][CN] in THF yielded crystals of the phenyl-substituted cyclic borate, tetra-ethyl-aza-nium 2,2,4,6-tetra-phenyl-1,3,5,2λ,4,6-trioxatriborinan-2-ide, CHN·CHBO or [NEt][B(μ-O)(CH)]. The mechanochemical reaction of BPh and [NEt][CN] without solvent produced crystals of tetra-ethyl-aza-nium cyano-diphenyl-λ-boranyl di-phenyl-borinate, CHN·CHBNO or [NEt][NCBPh(μ-O)BPh]. Reaction of BPh and KCN in THF in the presence of 2.2.2-cryptand (crypt) led to a crystal of bis-[(2.2.2-cryptand)potassium] 2,2,4,6-tetra-phenyl-1,3,5,2λ,4,6-trioxatriborinan-2-ide cyano-methyl-diphenyl-borate tetra-hydro-furan disolvate, 2CHKNO ·CHBO ·CHBN·2CHO or [K(crypt)][B(μ-O)(CH)][NCBPhMe]·2THF. The [NCBPh(μ-O)BPh] and (NCBPhMe) anions have not been structurally characterized previously. The structure of was refined as a two-component twin with occupancy factors 0.513 (1) and 0.487 (1). In , one solvent mol-ecule was disordered and included using multiple components with partial site-occupancy factors.