Abstract:
A range of volatile manganese(II) alkyl1 and allyl2 complexes have been prepared, with a view towards harnessing their high reactivity for elemental metal deposition using ALD (Atomic Layer Deposition; a uniquely-capable thin film deposition technique which relies upon repeated surface-based reactions between adsorbed molecules delivered in the vapor phase).3,4 The synthesis and structures of these complexes and their reactivity towards H2 and ZnEt2, including preliminary ALD studies, will be described. Reactions of the manganese(I) hydride complex, trans-[(dmpe)2MnH(C2H4)],5 with hydrosilanes were also explored with the initial goal of new ALD precursor development. However, these reactions proved to be of fundamental interest in their own right, affording the first group 7 silylene complexes, [(dmpe)2MnH(=SiR2)],6 and the disilyl hydride species [(dmpe)2MnH(SiH2R)2].7 Subsequent reactions with saturated (H2, hydrosilanes) and unsaturated (carbodiimide, CO2, CNR, ethylene, NHC) reagents led to a broad range of products, including the only isolated examples of first row transition metal complexes bearing sterically/electronically unstabilized silene ligands; [(dmpe)2MnH(HMeC=SiR2)].6 The mechanisms of these reactions, and metal–ligand bonding in the products will be discussed.
References:
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Price, J. S.; Emslie, D. J. H.; Vargas-Baca, I.; Britten, J. F. [(dmpe)2MnH(C2H4)] as a Source of a Low-Coordinate Ethyl Manganese(I) Species: Reactions with Primary Silanes, H2, and Isonitriles, Organometallics 2018, 37, 3010-3027.