132492-35-4Relevant academic research and scientific papers
Hydrochalcogenide and hydride hydrochalcogenide derivatives of rhodium
Di Vaira, Massimo,Peruzzini, Maurizio,Stoppioni, Piero
, p. 1001 - 1007 (2008/10/08)
By the reaction of hydrochalcogenide solutions with the (pp3)Rh cationic species [pp3 = tris(2-(diphenylphosphino)ethyl)phosphine, P(CH2CH2PPh2)3] the hydrochalcogenide compounds [(pp3)RhXH] [X = S (1), Se (2), Te (3)] have been obtained. The crystal structures of 1-3 were elucidated through complete X-ray analyses. The isomorphous compounds 1-3 crystallize in the hexagonal P63 space group with Z = 2 and the following lattice constants. 1: a = 13.524 (6), c = 12.119 (8) ?. 2: a = 13.542 (6), c = 12.188 (7) ?. 3: a = 13.573 (6), c = 12.346 (6) ?. In all complexes the metal atom exhibits a trigonal-bipyramidal coordination geometry with the three terminal phosphorus atoms of the ligand in the equatorial plane and the apical phosphorus atom of the same ligand and the chalcogen atom of the XH group in the axial positions. Complexes 1-3 react with CF3SO3H, yielding the rare hydride hydrochalcogenide compounds [(pp3)Rh(H)(XH)]CF3SO3 [X = S (5), Se (6), Te (7)]. On the basis of their IR and NMR data, these are assigned an octahedral geometry with the hydride and hydrochalcogenide ligands in cis positions, the four P atoms of the pp3 ligand occupying the remaining coordination sites. Compounds 5 and 6 are also obtained by reacting the (pp3)Rh cationic species with H2X (X = S, Se). Complexes 1 and 2 react with CF3SO3CH3, yielding the cis hydride methylchalcogenide derivatives [(pp3)Rh(H)(XCH3)]CF3SO3 [X = S (8), Se (9)]. The reactions prove that the electrophilic attack on hydrochalcogenide compounds 1-3 occurs on a lone pair of the chalcogen atom rather than on the sterically hindered metal center so that the final products are obtained through an internal oxidative addition.
