Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85747 Garching b. München, Germany.
J Am Chem Soc. 2009 Dec 9;131(48):17552-3. doi: 10.1021/ja908644n.
The dihydrido amine complex [Ru(H)(2)PMe(3){HN(CH(2)CH(2)P(i)Pr(2))(2)}] and H(2)O exhibit highly unusual, stereoselective H(+)/H(-) exchange, as derived using (1)H 2D EXSY NMR spectroscopy. While H(RuA) rapidly exchanges with H(2)O [k = 337(20) L mol(-1) s(-1)], no direct H(RuB)/H(2)O proton exchange was detected. Methylation of the pincer amine nitrogen results in unselective slow exchange of both hydrides with H(2)O. These results emphasize the important role of hydrogen bonding of N with Brønsted acids (e.g., water) for heteroloytic H(2) activation with Ru-amide hydrogenation catalysts, which was confirmed computationally.
二氢胺配合物[Ru(H)(2)PMe(3){HN(CH(2)CH(2)P(i)Pr(2))(2)}]和 H(2)O 表现出非常不寻常的、立体选择性的 H(+)/H(-)交换，这是通过 (1)H 2D EXSY NMR 光谱学得出的。虽然 H(RuA)与 H(2)O 快速交换 [k = 337(20) L mol(-1) s(-1)]，但没有检测到直接的 H(RuB)/H(2)O 质子交换。钳形胺氮的甲基化导致与 H(2)O 的两个氢化物的无选择性缓慢交换。这些结果强调了氢键与 Brønsted 酸（例如水）对 Ru-酰胺氢化催化剂的异裂 H(2)活化的重要作用，这一点通过计算得到了证实。
