Metal-metal bonds

The presence of multiply bonded dimetal units in materials offers opportunities for tuning properties of solids. Materials containing molybdenum-molybdenum quadruple bonds have recently begun being reported. This thesis reports the products of the reactions of dimethyl sulfide (DMS), acetonitrile (ACN) and acetate complexes, Mo2CI4(DMS)4, Mo2(ACN)10ABF4, and Mo2(0Ac)4
with 2,2';6,2"-terpyridine, 4'-phenyl 2,2';6,2"-terpyridine, 2,3,5,6-tetrakis (alpha-pyridyl) pyrazine and 1,3-bis(4-methylimino)isoindoline. Among these ligands, 2,3,5,6-tetrakis (alpha-pyridyl) pyrazine may lead to linear arrays of metal-metal bonds as well as other ordered structures. 1H-NMR, electronic absorption, and infrared data will be quoted to support any structural assignments.

The planar, dinuclear, tridentate ligands, 1,3,5,7-tetrakis(2-pyridylimino)benzodipyrrole (TAII) and 1,3,5,7-tetrakis(4,6-dimethyl-2-pyridylimino)benzodipyrrole (DiMeTAII) were synthesized and characterized as were all intermediates characterized by both infrared and 1H-NMR spectra. Evidence is presented for the formation of Mo4(OAc)6-(DiMeTAII) (I), the dinuclear analog of Mo2(OAc)3-BAII using UV/Vis to show the delta--->delta* transition typical of the quadruple bond and for the determination of percent molybdenum which is consistent with the proposed structure. A review of recent studies into the field of quadruply bonded metal containing polymers will be discussed along with application of compound (I) in this field.