Synthesis and Reactivity of Monocarbollide Carbonyl Complexes of Iron and Molybdenum with Icosahedral Frameworks

Abstract

The [NEt4]+ (1a), [NHMe3]+ (1b), and [N(PPh3)2]+ (1c) salts of the monoanion [Fe(CO)3(η5-7-CB10H11)]- have been prepared via the reaction between [Fe3(CO)12] and [NHMe3][nido-7-CB10H13] in THF (tetrahydrofuran). The complexes [N(PPh3)2][Fe(CO)2(L)(η5-7-CB10H11)] (L = PPh3 (2), CNBut (3)) were obtained by treating 1c in THF with PPh3 and CNBut, respectively, in the presence of Me3NO. The compound [N(PPh3)2][Mo(CO)4(η5-7-CB10H11)] (4) has been synthesized from [Na]3[nido-7-CB10H11] and [Mo(CO)3(NCMe)3] in the presence of CO and with addition of HBF4·Et2O and [N(PPh3)2]Cl. An X-ray diffraction study established that in the anion of 4 the Mo atom is coordinated on one side by the four CO molecules and on the other by a nido-7-CB10H11 carborane in a η5 manner. In reactions with PPh3 and CNBut, the salt 4 gives the species [N(PPh3)2][Mo(CO)3(L)(η5-7-CB10H11)] (L = PPh3 (5a), CNBut (6)). Salts of the anions [Fe(CO)3(η5-7-CB10H11)]- and [Mo(CO)3(PPh3)(η5-7-CB10H11)]- react with donor molecules (THF, OEt2, SMe2) i...