Department of Chemistry, Section of Inorganic and Analytical Chemistry, University of Ioannina, 45110, Greece.
Dalton Trans. 2010 Oct 14;39(38):9032-8. doi: 10.1039/c0dt00574f. Epub 2010 Aug 24.
The treatment of the trichloro-1,3,5-triazine with N-methylhydroxylamine hydrochloride results in the replacement of the three chlorine atoms of the triazine ring with the function -N(OH)CH(3) yielding the symmetrical tris-(hydroxyamino)triazine ligand H(3)trihyat. Reaction of the ligand H(3)trihyat with NaV(V)O(3) in aqueous solution followed by addition of Ph(4)PCl gave the mononuclear vanadium(V) compound Ph(4)P[V(V)O(2)(Htrihyat)] (1). The structure of compound 1 was determined by X-ray crystallography and indicates that this compound has a distorted square-pyramidal arrangement around vanadium. The ligand Htrihyat(2-) is bonded to vanadium atom in a tridentate fashion at the triazine ring nitrogen atom and the two deprotonated hydroxylamido oxygen atoms. The high electron density of the triazine ring nitrogen atoms, which results from the resonative contribution of electrons of exocyclic nitrogen atoms, leads to a very strong V-N bond. The cis-V(V)O(2)(Htrihyat) species exhibits high hydrolytic stability in aqueous solution over a wide pH range, 2.5-11.5, as was evidenced by potentiometry.
用 N-甲基羟胺盐酸盐处理三氯-1,3,5-三嗪，导致三嗪环上的三个氯原子被-N(OH)CH(3)取代，生成对称的三-(羟氨基)三嗪配体 H(3)trihyat。配体 H(3)trihyat 与 NaV(V)O(3)在水溶液中反应，然后加入 Ph(4)PCl，得到单核钒(V)化合物 Ph(4)P[V(V)O(2)(Htrihyat)] (1)。化合物 1 的结构通过 X 射线晶体学确定，表明该化合物在钒原子周围具有扭曲的四方锥排列。配体 Htrihyat(2-)以三齿方式与三嗪环氮原子和两个去质子化的羟氨基氧原子键合在钒原子上。由于环外氮原子的电子共振贡献，三嗪环氮原子具有很高的电子密度，导致非常强的 V-N 键。顺式-V(V)O(2)(Htrihyat)物种在很宽的 pH 范围内（2.5-11.5）在水溶液中表现出很高的水解稳定性，这一点通过电位法得到了证明。
