In organic chemistry, atoms other than carbon and hydrogen are generally referred to as heteroatoms. The most common heteroatoms are nitrogen, oxygen and sulfur. Now I present to you an article called Heteroleptic poly(pyrazolyl)borate derivatives of the lanthanides. Structural and electronic spectral studies of some salicylaldehyde complexes, published in 1996-02-21, which mentions a compound: 18583-60-3, mainly applied to crystal structure europium pyrazolylborato salicylaldehydato; rare earth pyrazolylborato salicylaldehydato preparation, Application In Synthesis of Potassiumtris(1-pyrazolyl)borohydride.
[Ln{HB(pz)3}2L] [pz = pyrazol-1-yl; L = salicylaldehydate, Ln = Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb or Lu; L = 5-methoxysalicylaldehydate (mosal), Ln = Y, Pr, Nd, Sm, Eu, Gd, Tb, Yb or Lu] were synthesized and the crystal structure of [Eu{HB(pz)3}2(mosal)] determined The Eu ion is eight-coordinate with Eu-O distances of 2.266(5) and 2.402(5) Å; polytopal anal. indicates that the coordination geometry is best described as dodecahedral. The solid-angle sum of 0.768 is close to the norm for eight-coordination. These structural parameters were compared with those calculated for the previously reported binuclear complex [{Sm[HB(pz)3]2(O2CPh)}2] and estimated for its monomeric counterpart, which is as yet unknown. The use of such data in predicting when complexes of this type will dimerize was assessed. Electronic spectra of the Nd complexes revealed <1% covalency in the metal-ligand bonding and emission spectral data are reported for the Eu and Tb complexes. The article 《Heteroleptic poly(pyrazolyl)borate derivatives of the lanthanides. Structural and electronic spectral studies of some salicylaldehyde complexes》 also mentions many details about this compound(18583-60-3)Application In Synthesis of Potassiumtris(1-pyrazolyl)borohydride, you can pay attention to it, because details determine success or failure
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Piperazine – Wikipedia,
Piperazines – an overview | ScienceDirect Topics