(NâN)PtIV(CH3)2(OH)2 â x(OCH3)x
(x
= 0, 1; NâN = bipy, 4,4â²-(CH3)2bipy, 4,4â²-tBu2bipy, ArNC(CH3)âC(CH3)NAr (Ar = 3,5-(CF3)2C6H3, 3,5-(CH3)2C6H3, 2,6-(CH3)2C6H3) complexes have been prepared by oxidation of the appropriate (NâN)PtII(CH3)2 complexes using H2O2/H2O. In methanol, the hydroxoâmethoxy complexes are formed (x
= 1), whereas in acetone, the dihydroxo complexes are formed (x
= 0). A single-crystal X-ray structure determination establishes the structure of (4,4â²-(CH3)2bipy)PtIV(CH3)2(OH)2 as a dihydroxo compound with octahedral geometry, with the hydroxo ligands occupying apical coordination sites. The acidities of the protonated bipy hydroxo complexes, (4,4â²-R2bipy)PtIV(CH3)2(OH)(OH2)+ cations, were determined in methanol. The acidities closely matched that of Cl2CHCOOH (pKa
= 6.38 in CH3OH).
通过将适当的 (N–N)PtII(
CH3)2 配合物在
H2O2/
H2O 条件下
氧化,制备了 (N–N)PtIV( )2(OH)2–x(O )x (x = 0, 1; N–N = bipy, 4,4′-( )2bipy, 4,4′-tBu2bipy, ArNC( )–C( )NAr (Ar = 3,5-(
CF3)2C6H3, 3,5-( )2C6H3, 2,6-( )2C6H3) 配合物。在
甲醇中,形成了羟
氧基甲
氧基配合物 (x = 1),而在
丙酮中,则形成了二羟基配合物 (x = 0)。通过单晶 X 射线结构测定,确定了 (4,4′-( )2bipy)PtIV( )2(OH)2 为具有八面体几何结构的二羟基化合物,其中羟基
配体占据顶端配位位置。在
甲醇中,测定了质子化的 bipy 羟基配合物,(4,4′-R2bipy)PtIV( )2(OH)(OH2)+ 阳离子的酸度。酸度与 Cl2CHCOOH 的酸度非常接近(在 OH 中的 pKa = 6.38)。