Chemistry Department Seminar

It will be argued that the amide ligand (tBu2PCH2SiMe2)2N-1, “PNP” creates a sterically protected (from tBu) and electron rich (from amide N donation) metal center. For Ru(II), the compound (PNP)RuCl is unusual in being “doubly unsaturated,” 4 coordinate and planar, and this leads to facile binding of PhCN, C2H4, and N2, but remarkably “deeper” reactions with H2, with terminal alkynes, and with Me3SiN3. The analogous osmium chemistry shows dramatic differences, leading into the chemistry of radical species, and rhodium shows formation of an adduct with an arene C-H bond coordinating to the metal, as well as C-H bond cleavage ability. Understanding all of this reaction chemistry is enhanced by concurrent DFT calculations. Generalization of the above reactivity principles is possible by studies with lighter transition elements Fe, Co and Ni, which, in turn, leads to results relevant to the concept of a chemical reaction being “spin forbidden.”