Acidolyis and oxygen atom transfer reactivity of a diiridium hydroperoxo complex.
Acidolyis and oxygen atom transfer reactivity of a diiridium hydroperoxo complex.
复制标题
二铱氢过氧络合物的酸解和氧原子转移反应性。
作者：
Thomas S. Teets;D. Nocera
Ir(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)H (1, tfepma = CH(3)N[P(OCH(2)CF(3))（2)](2)）的氧化得到Ir(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)(OOH)(2)，第一个可分离的铱氢过氧配合物。该配合物将一个氧原子转移到三苯基膦上，高产出三苯基膦氧化物和Ir(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)(OH)(3)。2与酸反应诱导O-O键断裂，初步形成[Ir(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)(OH(2))]Cl(4)，经核磁共振谱鉴定。以HCl为酸源，氯离子取代水形成Ir(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(4)(5)的伪c （2h）异构体。以2,6-氯化镥为酸，初始形成配合物4，并被共轭碱去质子化生成主要产物3。
Oxygenation of Ir(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)H (1, tfepma = CH(3)N[P(OCH(2)CF(3))(2)](2)) furnishes Ir(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)(OOH) (2), the first isolable iridium hydroperoxo complex. This complex transfers an oxygen atom to triphenylphosphine, producing triphenylphosphine oxide and Ir(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)(OH) (3) in high yield. Reaction of 2 with acid induces cleavage of the O-O bond, initially forming [Ir(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)(OH(2))]Cl (4), which was identified by NMR spectroscopy. With HCl as the acid source, the chloride anion displaces water to form the pseudo-C(2h) isomer of Ir(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(4) (5). With 2,6-lutidinium chloride as the acid, complex 4 forms initially and is deprotonated by the conjugate base to afford 3 as the major product.