Hetterscheid Dennis G H, Hanna Brian S, Schrock Richard R
Department of Chemistry 6331, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, Massachusetts 02139, USA.
Inorg Chem. 2009 Sep 7;48(17):8569-77. doi: 10.1021/ic900468n.
[HIPTN(3)N]Mo(N(2)) (MoN(2)) (HIPTN(3)N = (HIPTNCH(2)CH(2))(3)N where HIPT = 3,5-(2,4,6-i-Pr(3)C(6)H(2))(2)C(6)H(3)) reacts with dihydrogen slowly (days) at 22 degrees C to yield [HIPTN(3)N]MoH(2) (MoH(2)), a compound whose properties are most consistent with it being a dihydrogen complex of Mo(III). The intermediate in the slow reaction between MoN(2) and H(2) is proposed to be [HIPTN(3)N]Mo (Mo). In contrast, MoN(2), MoNH(3), and MoH(2) are interconverted rapidly in the presence of H(2), N(2), and NH(3), and MoH(2) is the lowest energy of the three Mo compounds. Catalytic runs with MoH(2) as a catalyst suggest that it is competent for reduction of N(2) with protons and electrons under standard conditions. [HIPTN(3)N]MoH(2) reacts rapidly with HD to yield a mixture of [HIPTN(3)N]MoH(2), [HIPTN(3)N]MoD(2), and [HIPTN(3)N]MoHD, and rapidly catalyzes H/D exchange between H(2) and D(2). MoH(2) reacts readily with ethylene, PMe(3), and CO to yield monoadducts. Reduction of dinitrogen to ammonia in the presence of 32 equiv of added hydrogen (vs Mo) is not catalytic, consistent with dihydrogen being an inhibitor of dinitrogen reduction.
[HIPTN(3)N]Mo(N(2))（MoN(2)）（HIPTN(3)N = (HIPTNCH(2)CH(2))(3)N，其中HIPT = 3,5-(2,4,6-异丙基(3)C(6)H(2))(2)C(6)H(3)）在22℃下与氢气缓慢反应（数天），生成[HIPTN(3)N]MoH(2)（MoH(2)），该化合物的性质与它作为Mo(III)的二氢配合物最为一致。MoN(2)与H(2)之间缓慢反应的中间体被认为是[HIPTN(3)N]Mo（Mo）。相比之下，在H(2)、N(2)和NH(3)存在的情况下，MoN(2)、MoNH(3)和MoH(2)会迅速相互转化，并且MoH(2)是这三种Mo化合物中能量最低的。以MoH(2)作为催化剂的催化实验表明，在标准条件下它能够用质子和电子还原N(2)。[HIPTN(3)N]MoH(2)与HD迅速反应，生成[HIPTN(3)N]MoH(2)、[HIPTN(3)N]MoD(2)和[HIPTN(3)N]MoHD的混合物，并迅速催化H(₂)和D(₂)之间的H/D交换。MoH(2)很容易与乙烯、PMe(3)和CO反应生成单加合物。在添加32当量氢气（相对于Mo）的情况下，将二氮还原为氨不是催化反应，这与二氢是二氮还原的抑制剂一致。
