Carbonylvanadium, -mangan- und -molybdänkomplexe mit den Liganden o-C6H4EPh2(E'Ph2) (E,E' = P, As, Sb, Bi) und cis-Ph2PCH=CHPPh2 / Carbonylvanadium, -manganese and -molybdenum Complexes of the Ligandso-C6H4EPh2(E'Ph2) (E,E' = P, As, Sb, Bi) und cis-Ph2PCH=CHPPh2

Abstract

Abstract The photo-induced reaction between the complexes [Et4N][V(CO)6] (1), η5-C5H5V(CO)4 (2), η5-C5H5Mn(CO)3 (3) or η5-C5H5Mo(CO)3CH3 (4) and the ligands o-C6H4EPh2(E'Ph2) (E = E' = P: a; E = P, E'=As: b; E = E ' = As: C; E = P, E ' = S b : d; E = P, E ' = Bi: e; E = As, E' = Sb: f) and cis-Ph2PCH = CHPPh2 (g), L, yields - depending on the steric requirement of L - the compounds (M}L ({M} = cis-V(CO)4-, cis-CpV(CO)2, CpMn(CO), CpMo(CO)CH3; L = a, b, c, g), {M'}L ({M'} = V(CO)5-, L - d; {M'} - CpV(CO)3, L - d, e; {M'} = CpMn(CO)2, L = e) or mixtures of {M}L and (M'}L ({M}, {M'} = V(CO)4,5, L = e,f; {M}, {M'} = CpV(CO)2,3, L = f). In the mono-substituted species {M'}L coordination (as indicated by the 51V NMR spectra) occurs through EPh2 and E'Ph2, which is explained by a reaction path via a labile chelate 5-ring structure. Shielding of the 51V nucleus decreases in the order g > SbPh2 > PPh2 > AsPh2 > BiPh2 (derivatives of 1) and g > SbPh2 > PPh2 > BiPh2 >AsPh2 (derivatives of 2), and is smaller in the rigid chelates incorporating the o-phenylene ligands than in the more flexible structures of phospha- and arsabutane complexes. This fact is discussed in terms of hindered σ-overlap due to distortion of the EVE angle, which also results in an increase of CO valence force constants in rigid chelates. 31P coordination shifts increase according to dppe < a < g and arphos < b (dppe = Ph2P(CH2)2PPh2, arphos = Ph2As(CH2)2PPh2). 31P NMR spectra of the molybdenum complexes suggest that the basic geometry for 4a and 4b likely is tetragonal pyramidal, while the preferred structure for 4g appears to be the trigonal bipyramid with the ligand in equatorial positions. The crystal and molecular structure of 1a is reported. The complex crystallizes in the space group C2/c (a = 2196.0, b= 1080.1, c = 2022.7 pm, β= 124.6°). The most striking result is the small PVP angle of 80.8 (0.2)°. Optimized methods for the synthesis of the ligands a-f are described; the ligands are characterized by their mass spectra.